UM0241 User manual
ST7538 Power Line Modem Demokit Graphical User Interface (GUI)
Introduction
The "ST7538/40 FSK Power Line Modem Demo Kit" is a software tool that allows interfacing one or more ST Power Line Modem (PLM) Demo Boards with a Personal Computer. Only PLM Demo Boards equipped with ST7538 and ST7540 devices are supported. The typical Application Environment consists of a PC that communicates, through a ST7 microcontroller placed on a general purpose board called "EVALCOMMBOARD" (see Section 1.5), with a Power Line Modem Board equipped with ST7538 or ST7540 products as shown in Figure . The interface used to communicate between the PC and the EVALCOMMBOARD is the RS-232 (USB interface will be supported in future). At start-up, the Software recognizes automatically which type of device is connected to PC and modifies its appearance differently for the ST7538 or the ST7540. This document describes the ST7538 operating mode (see Section 1.5). A schematic of the application environment
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T7 C
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With the "ST7538/40 FSK Power Line Modem Demo Kit" it is possible to:
Write/read ST7538 (or ST7540) Control Register Open a Tx session Open a Rx session Open a Ping session (minimum two devices required)
July 2006
Rev 1
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Contents
UM0241
Contents
1 Installation information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.1 1.2 1.3 1.4 1.5 Software license agreement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Installing the software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Release information and boards supported . . . . . . . . . . . . . . . . . . . . . . . . 8 Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 3
Commonly used terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 User interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1 3.2 3.3 Menu bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Toolbar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Status bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4
Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 4.2 Selecting the COM port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Setting the Control Register parameters . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8 4.2.9 4.2.10 4.2.11 4.2.12 4.2.13 4.2.14 4.2.15 4.2.16 Carrier Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Baud rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Deviation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Interfacing mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Watchdog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Transmission timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Detection method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Frequency detection time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Zero crossing synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Output clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Packet mode baud rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Packet length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Packet mode enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Sensitivity mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Pre-filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Limitations on Control Register parameters . . . . . . . . . . . . . . . . . . . . . 19
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Contents
4.3 4.4 4.5 4.6
Selecting the Dual Channel option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Monitoring events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Using the Control Register String . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Reading/Writing Control Register parameters . . . . . . . . . . . . . . . . . . . . . 22
5 6 7
Transmission sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Receive sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Ping sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.1 Opening a Ping Master session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.1.1 7.1.2 Ping Master parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Star ting a Master Ping session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
7.2
Opening a Ping Slave session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
7.2.1 7.2.2 Ping Slave parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Star ting a Slave Ping session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
7.3 7.4
Ping protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Ping session flowcharts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
8
Communication session examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.1 Setup procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.1.1 8.1.2 8.1.3 Required hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Hardware setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Software setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.2 8.3 8.4
Communication session without Frame Synchronization . . . . . . . . . . . . . 35 Communication session with Frame Synchronization . . . . . . . . . . . . . . . 37 Ping session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
9
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
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List of tables
UM0241
List of tables
Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Table 8. Table 9. Table 10. Table 11. Table 12. Table 13. Table 14. Table 15. Table 16. Table 17. Table 18. Table 19. Table 20. Commonly used terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Menu bar commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Summary of Control Register parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Carrier frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Baud rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Deviation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Mains interfacing mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Watchdog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Transmission timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Detection method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Frequency detection time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Zero crossing synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Output clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Sensitivity mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Pre-filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Limitations on control register parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Summary of events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Ping master parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Ping slave parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
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UM0241
List of figures
List of figures
Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Figure 25. Figure 26. Figure 27. Main window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Toolbar controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 ST7538 status bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 COM selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Device selection and communication error during COM selection . . . . . . . . . . . . . . . . . . . 14 Control Register window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 ST7538 Control Register parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Dual channel selection panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Events panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Write control register string and parameters position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Control register writing/reading procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Read CTRL Register dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Transmission Monitor dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Receive Monitor dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Ping windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Ping Master dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Ping slave window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Ping message format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Ping master loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Ping slave loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Communication setup: COM selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Control Register dialog boxes after setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Communication without Frame Synchronization example . . . . . . . . . . . . . . . . . . . . . . . . . 36 Demodulation timings for RX with preamble detection (@2400 baud) . . . . . . . . . . . . . . . . 37 Communication with Frame Synchronization example . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Ping master session and save statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Ping slave session and save statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
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Installation information
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1
1.1
Installation information
Software license agreement
1. Impor tant Before loading this software you have to carefully read and agree to the following terms and conditions which will be then automatically agreed on by loading this Software or any portion thereof. If you do not agree to the terms of this Agreement, do not install or use anyhow this software or any portion thereof. 2. License grant ST grants you a non-exclusive, royalty-free, worldwide license to this software written for ST products ("Software"). You shall have the right to use, copy, modify and distribute the Software with ST products only. All ST Software will be required to contain the ST Copyright notice which shall not be removed therefrom for any reason. You acknowledge that the Software is not designed nor is authorized for use in life supporting devices or systems. 3. Ownership and copyright of software Title to the Software and all copies thereof remain with ST. The Software is copyrighted and protected by worldwide copyright laws and international treaty provisions. Except as expressly provided herein, ST does not grant any express or implied right to you under ST patents, copyrights, trademarks, or trade secret information. 4. Warranties and liabilities ST makes no warranty express or implied including but not limited to, any warranty of (i) merchantability or fitness for a particular purpose and/or (ii) requirements, for a particular purpose in relation to the Software which is provided ON AN "AS IS" BASIS. All warranties, conditions or other terms implied by law are excluded to the fullest extent permitted by law. ST shall not be liable for any claim made by you and/or against you by a third party, in relation to the Software under this Agreement. You take responsibility for the suitability, selection, use and management of the Software and the results obtained there from as well as their combination and the combination of the elements thereof with other apparatus, equipment, products, programs and services. Nothing contained in these terms shall be construed as a warranty or representation by ST as to the validity or scope of any and all IPR in respect of which a license is herein granted or constitutes a warranty or representation that any manufacture, use or sale by you hereunder shall be free from infringement of any Intellectual Property Rights (IPR) other than those under which and to the extent to which rights thereto are granted hereunder or constitute an agreement to bring or prosecute actions or suits against third parties for infringements or confer any right upon a party to use in advertising, publicity or other medium, any name trademark or trade name or any other contraction abbreviation or simulation thereto of the other party or confer by implication estoppel or otherwise upon you any license or other right under any and all IPR except the licenses and rights expressly granted hereunder to you. In no event shall ST be liable for any damages whatsoever (including, without limitation, damages for loss of business revenue or profits, business interruption, loss of business information or other pecuniary loss) arising out of the use of or the inability to use the Software as part of an ST application. ST does not assume any responsibility for any errors that may appear in the Software nor any responsibility to support or update the Software. ST
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Installation information retains the right to make changes to the Software and its test specifications at any time, without notice. 5. Entire agreement This Agreement constitutes the entire agreement with ST and supersedes any prior or contemporaneous oral or written agreements with respect to the subject matter of this Agreement. 6. Support Under this Agreement, ST is under no obligation to assist in the use of the Software, to provide you support of the Software, or to provide maintenance, correction, modification, enhancement, or upgrades to the Software. Any action taken by ST in this respect will be unilaterally taken and subject only to ST assessment - without any notice to you. Any such action shall be considered as Software and will automatically be subject to this Agreement. 7. Termination of this license ST is entitled to terminate this Software License Agreement at any time if you are in breach of any of the terms of this Agreement. Upon termination, you will immediately destroy the Software. 8. Export regulations You undertake to comply with all applicable laws, regulations, decrees and ordinances related to your use of the Software. 9. Applicable laws Any dispute arising out of or in connection with this Agreement which could not be amicably settled shall be finally settled under the Rules of Conciliation and Arbitration of the international Chamber of Commerce by one or more arbitrators appointed in accordance with the said Rules which the Parties know and elect irrevocably. Such arbitration shall take place in Paris and be held in English.
1.2
System requirements
A Personal Computer (PC) including:
one or more RS-232 serial ports a CD-ROM reader a Hard Disk with at least 20 MBytes of free space Screen resolution 800x600 or higher Operating System Windows NT/2000/XP Adobe Acrobat Reader release 4.0 or more recent
1.3
Installing the software
To install the software: 1. 2. 1. Inser t the ST7538/40 Demo Board CD-ROM in your PC and execute the setup.exe file. Follow the instructions displayed by the application wizard. Execute the ST7538/40 PLM Demo Kit program (Start Programs ST7538_40 FSK PowerLine Modem Demo Kit ST7538_40 FSK PowerLine Modem Demo Kit).
To run the software:
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Installation information
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1.4
Release information and boards supported
This document refers to Release 3.19 of the "ST7538/40 FSK PowerLine Modem Demo Kit". The following Evaluation Boards are supported by the "ST7538/40 FSK PowerLine Modem Demo Kit":
ST7538 Evaluation Board rev. 2.1 & rev. 2.2 EVALCOMMBOARD rev. 1.1 + EVALST7538DUAL rev. 3.1 Dual Channel EVALCOMMBOARD rev. 1.1 + EVALST7540-1 rev. 2.1
1.5
Reference documents
For more information about the EVALCOMMBOARD please refer to "UM0240 User Manual Industrial Communication Board - EVALCOMMBOARD" For ST7540 working mode, please refer to "UM0239 User Manual ST7540 Power Line Modem Demokit GUI".
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UM0241
Commonly used terms
2
Commonly used terms
Table 1 describes some of the commonly used terms regarding Power Line Communication and other terms used in this document: Table 1.
Term FCS
Commonly used terms
Description Frame Check Sequence. An error detection scheme that uses parity bits generated by polynomial encoding of digital signals. Forward Error Correction. A system of error control for data transmission wherein the receiving device has the capability to detect and correct any character or code block that contains less than a predetermined number of symbols in error. FEC is accomplished by adding bits to each transmitted character or code block, using a predetermined algorithm. Medium Access Control. A service feature or technique used to permit or deny use of a communication medium. The electrical network that supplies homes and businesses with power. Program that measures the time elapsed between the transmission of multiple packets to a remote device and the return to origin (real meaning). In this document, the term ping is used to describe a packet exchange process between a Master device and one or more Slave devices, collecting statistical data about the integrity of packets. Power Line Communication. Communication performed between two or more nodes of the electrical network. Power Line Modem. A device able to transmit and receive information across the electrical network. To ensure reliability of communication, digital data are transformed modulating a carrier signal in transmission and demodulating such a carrier in reception.
FEC
MAC Mains
Ping
PLC
PLM
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User interface
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3
User interface
Figure 1 shows the main window of the "ST7538/40 FSK PowerLine Modem Demo Kit" program. Figure 1. Main window
PROGRAM SECTIONS: 1 2 1 2 3
MENU BAR TOOLBAR STATUS BAR
3
The Main Window consists of: 1. 2. 3. A menu bar A toolbar A status bar
The following sections provide a complete description for each component.
3.1
Menu bar
The Menu Bar enables the user to:
Select the COM port for communication with the Demo Board Modify the size of the Toolbar Save the last configuration used when exiting the program (GUI) View help and information about this Software and ST7538 and ST7540 devices Exit the program
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User interface Table 2 summarizes the list of commands available in the menu bar and their functions: Table 2.
Menu voice File Exit COM settings Commands
Menu bar commands
Submenu voice Function Exits from the Program Opens COM port selected and begins the communication with the Demo Board (ports available from COM1 to COM4) Selects the size of the toolbar (small, medium or large) On exit saves the current program settings(1) Opens the "ST7538 PowerLine Modem Demo Kit GUI- User Manual" Opens this document Opens ST7538 specification document Opens ST7540 specification document Shows information about Software Release
Toolbar size Save on Exit ST7538 Demo kit GUI User Manual ST7540 Demo kit GUI User Manual
Help
ST7538 Datasheet ST7540 Datasheet About
1. Settings saved refer to all controls present in the "ST7538/40 FSK PowerLine Modem Demo Kit" tool.
3.2
Toolbar
The Toolbar is used to access all sections of the program. The sections available are:
Receiving session Transmission session Control Register access Ping session Toolbar controls
TX SESSION PING SESSION
Figure 2.
RX SESSION
CR ACCESS
1
Toolbar sections are not available until the correct COM port is selected as described in Section 4.1: Selecting the COM port on page 13.
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3.3
Status bar
The Status Bar shows information about software, firmware and about the link between PC and the Evaluation Board. Figure 3. ST7538 status bar
COM port Selected
Softw are release
Firmw are release
Link status
The left side of the Status Bar indicates the selected COM port by means of Command COM Settings menu voice. The SW version field indicates the software release. To the right, a text string shows the device used (ST7538 in this case) and the the Firmware release of ST7 microcontroller equipped on IBU Communication Board. The LED to the right of the Status Bar (Demo Link) indicates the status of communication between PC and Evaluation board. If a communication error occurs (bad or no response from the MCU to PC), this LED turns from green to red.
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Getting started
4
4.1
Getting started
Selecting the COM port
The first step required for using the PLM Demo Kit program is to select the correct COM port for communication between the PC and the ST7538/40 PLM Demo Board and the ST7 MCU EVALCOMMBOARD.
Warning:
When running the program for the first time, the user must perform a Control Register Writing operation before being able to access the other GUI sections. This action is mandatory because the only communication interface available from the MCU on EVALCOMMBOARD to ST7538 is synchronous, while the default Mains interface of ST7538 is asynchronous. The only action that can be performed before a Control Register Writing is a Control Register Reading, because Control Register Access is always synchronous.
Figure 4.
COM selection
1
Once the correct COM port is selected, the program starts communication with the EVALCOMMBOARD and automatically recognizes the type of device (ST7538 or ST7540) on the PLM Board and the firmware revision of the ST7 microcontroller (on EVALCOMMBOARD). The status bar also displays this data as shown in Figure 3. If a communication problem occurs during COM selection, e.g. if the Demo Board has not been properly connected to PC, a message box appears and the user must select the device to manage (see Figure 5). The user must select the ST7538 device to ensure correct program behavior (see Note 1). It is possible to control a maximum of four devices (from COM1 to COM4) using a single Personal Computer by launching four instances of the program. In order to identify the instances, a different window background color is used for every COM port. After the COM selection, the user can access all GUI sections.
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Getting started Figure 5. Device selection and communication error during COM selection
UM0241
COMMUNICATION ERROR
DEVICE SELECTION
Communication errors can occur at any time. The Device Selection message box appears if an error occurs only during the first COM selection. To ensure reliable communications, a link status LED is present on the Status Bar as shown in Figure 3. Note: 1 If an incorrect device is selected, the user must close and restart the Program in order to avoid undesired behavior.
4.2
Setting the Control Register parameters
To access to the ST7538 Control Register, click the REG button on the Toolbar. The main window then displays the Control Register dialog box as shown in Figure 6. Figure 6. Control Register window
ST7538 CONTROL REGISTER WINDOW
3 1
1. Control Register Params Panel 2. WR Control Register String 3. Events Panel
2 4 5
6
4. Write CR Button 5. Read CR Button 6. Dual channel selection
This dialog box enables the user to modify the Control Register parameters.
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UM0241 Figure 7. ST7538 Control Register parameters
Getting started
ST7538 CONTROL REGISTER PARAMETER PANEL a e m b h k c f l i g n d j o
This section describes each of the Control Register parameters. Table 3 provides a summary of each parameter, bit-by-bit, as appears in the Control Register string in binary format from MSB to LSB. Table 3.
Bits 2:0 4:3 5 6 8:7 10:9 11 13:12
Summary of Control Register parameters
Parameter Carrier Frequency Baudrate Deviation Watchdog Transmission Timeout Frequency Detection Time Zero Crossing Synchronization Detection Method 14 16:15 18:17 20:19 21 22 23 Bits Parameter Mains Interfacing Mode Output Clock Packet Mode Baud Rate Packet Length Packet mode enable Sensitivity Mode Pre-filter
Note:
Default values listed in this section refer to the ST7538 Power Line Transceiver.
4.2.1
Carrier Frequency
The Carrier Frequency parameter (Bits [2:0]) defines at which center frequency the signal is transmitted or received across the mains. If Dual Channel feature is disabled, the Carrier Frequency parameter must be set through the "ST7538 Control Register Parameter Panel". Otherwise, the "Dual Channel Selection" panel must be used. For more information, see Section 4.3: Selecting the Dual Channel option on page 19.
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Getting started Table 4. Carrier frequency
Value (kHz) 60 66 72 76 Bits 2 to 0 (MSB to LSB) 100 101 110 111
UM0241
Bits 2 to 0 (MSB to LSB) 000 001 010 011
Value (kHz) 82.05 86 110 132.5 (default)
4.2.2
Baud rate
The baud rate parameter (Bits [4:3]) defines the speed of communication. Table 5. Baud rate
Value (bps) Bits 4 to 3 (MSB to LSB) 10 600 11 Value (bps) 2400 (default) 4800
Bits 4 to 3 (MSB to LSB) 00 01
4.2.3
Deviation
The Deviation parameter (Bit 5) defines the frequency difference between the mark and the space frequency. When set to "0.5", the difference is one-half the Baud Rate value. Otherwise, the difference is the Baud Rate value itself. Table 6.
Bit 5 0 1 "0.5" (default) "1"
Deviation
Value
4.2.4
Interfacing mode
The (Mains) Interfacing mode (Bit 14) defines, when transmitting or receiving data across the Mains, if the timings are managed by ST7538 by means of CLR/T line (Synchronous mode) or by the host (Asynchronous mode). In Asynchronous mode, data enter directly in the FSK modulator in Transmission mode and are sent directly from the demodulator to the RxD line in Reception mode. In the current software/firmware release, only Synchronous interfacing mode is available. Due to the fact that Asynchronous Mains interfacing mode is the ST7538 default value, the user must write at least once to the CR (in Synchronous interface mode) before the GUI will perform any other action (except CR reading). Table 7.
Bit 14 0 1 Synchronous Asynchronous (default)
Mains interfacing mode
Value
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Getting started
4.2.5
Watchdog
The Watchdog parameter (Bit 6) enables the Watchdog function that generates an internal and external reset when the internal Watchdog timer expires. The Watchdog timer is reset by applying a negative pulse on pin WD.
Note:
The ST7 MCU Firmware (on EVALCOMMBOARD) automatically provides the Watchdog Timer Reset. Table 8.
Bit 6 0 1 Disabled 1.5 (default)
Watchdog
Value (sec)
4.2.6
Transmission timeout
The Transmission Timeout parameter (Bits [8:7]) defines the maximum time of continuous transmission before a Timeout event occurs. In this case, the transmission is interrupted and the device is set in RX mode. Table 9. Transmission timeout
Value (sec) Disabled 1 (default) Bits [8:7] 10 11 Value (sec) 3 Not used
Bits [8:7] 00 01
4.2.7
Detection method
The Detection method (Bits [13:12]) defines the way the modem notifies the presence of a carrier (CD) or preamble (PD) through the ST7538 CD/PD pin. If the Carrier detection method is selected, the CD/PD line becomes active when a signal with a harmonic component close to the programmed Carrier Frequency is detected on the RAI pin. If the Preamble detection method is selected, the CD/PD line becomes active when a signal with a carrier modulated at the programmed Baud Rate for at least 4 consecutive symbols ("1010" or "0101") is detected on the RAI pin. If the Detection method is conditioned CLR/T and RxD signals are enable only when CD/PD line is enable, otherwise CLR/T and RxD are always enabled. Table 10.
Bits [13:12] 00 01
Detection method
Value Carrier detection without conditioning Carrier detection with conditioning Bits [13:12] 10 11 Value Preamble detection without conditioning (default) Preamble detection with conditioning
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Getting started
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4.2.8
Frequency detection time
This parameter (Bits [10:9]) defines the time within which a carrier must be detected across the Mains before signalling it on ST7538 CD/PD pin. If the Preamble Detection method is selected, the CD/PD becomes active only if also a preamble is detected. For more information, see Section 4.2.7: Detection method. Table 11. Frequency detection time
Value (msec) 0.5 1 (default) Bits [10:9] 10 11 Value (msec) 3 5
Bits [10:9] 00 01
4.2.9
Zero crossing synchronization
This parameter (Bit 11) synchronizes transmissions with the Mains positive zero-crossing transition.
Note:
The Zero Crossing Synchronization function requires external circuitry that is not present in all Demo Boards. On PLM Demo Boards that do not support Zero Crossing Synchronization, this setting must be disabled. Table 12.
Bit 11 0 1 Disabled (default) Enabled
Zero crossing synchronization
Value
4.2.10
Output clock
The Output Clock parameter (Bits [16:15]) sets the ST7538 MCLK line frequency as a submultiple of the 16-MHz oscillator frequency or disables the output clock. Table 13.
Bits [16:15] 00 01
Output clock
Value (MHz) 16 8 Bits [16:15] 10 11 Value (MHz) 4 (default) Not used
4.2.11
Packet mode baud rate
This feature is not currently available. See Section 4.2.13: Packet mode enable.
4.2.12
Packet length
This feature is not currently available. See Section 4.2.13: Packet mode enable.
4.2.13
Packet mode enable
This feature is not currently available. This bit must always be set to `0' or Disabled.
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Getting started
4.2.14
Sensitivity mode
The Sensitivity Mode parameter (Bit 22) defines the low threshold for the FSK demodulator block. Table 14.
Bit 22 0 1 Normal Sensitivity (500 Vrms) (default) High Sensitivity (250 Vrms)
Sensitivity mode
Value
4.2.15
Pre-filter
The Pre-filter parameter (Bit 23) enables a pre-filter on the Reception path. Table 15.
Bit 23 0 1 Disabled (default) Enabled
Pre-filter
Value
4.2.16
Limitations on Control Register parameters
Cer tain parameters are limited during programming because either their functions are not supported by the tool. Table 16 lists these limitations. Table 16. Limitations on control register parameters
Parameter Mains Interface mode Limitation Only Synchronous Mains interface mode is supported
Packet Baud Rate, Packet Length Packet mode is not supported and Packet Mode Enable
4.3
Selecting the Dual Channel option
Cer tain ST7538 PLM Demo Boards(a) have the ability to select the central frequency of external coupling filter between two operating frequencies. In order to activate this function, the user must select the DUAL CH. check box in the Dual Channel selection pane, set the correct frequencies for each of the two channels. When Dual Channel function is enabled, a command of channel selection is transmitted each time the user pushes the Write Control Register button. When the Dual Channel feature is enabled, the Control Register is programmed according to the selected Dual Channel frequency.
a. PLM Eval Boards that support the Dual Channel feature have the suffix "DUAL" (i.e. "EVALST7538DUAL Rev. 3.1 Dual Channel")
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Getting started Figure 8. Dual channel selection panel
ST7538 DUAL CHANNEL SELECTION PANEL
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1
4.4
Monitoring events
By means of Events Panel LEDs it is possible to monitor the status of the Demo Board. The LEDs represent events occurred during the working session. Figure 9. Events panel
EVENTS PANEL
1
The LEDs are updated every time a communication is performed between the software tool and the Demo Board, except for the Link Monitor LED that it is activated also when the user modifies a Control Register parameter using the Control Register Parameters Panel. In this case, the Write Control Register String on the panel no longer corresponds to the ST7538 Control Register. For this reason, the Link Monitor LED is always enabled (red) at first run of the program. Table 17 lists possible events. Table 17.
Event Reset Event Reg OK Event Timeout Event
Summary of events
Description Event occurs when MCU of EVALCOMMBOARD is reset Event occurs when ST7538 Control Register content is corrupted Event occurs when a transmission session is longer than the Timeout value (CR Bits [8:7]) or a Thermal Shutdown event is detected Event occurs when: Write Control Register String does not correspond to ST7538 Control Register A reset or a communication problem event occurs
Link Monitor
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UM0241
Getting started If a communication problem occurs, a message box describing the issue appears. In this case, the user must try again to perform the same operation that caused the problem until no more message boxes appear and the Link Monitor LED becomes green.
Note:
If communication problems persist, the user can reset the microcontroller on EVALCOMMBOARD by pushing the RES button. After this operation, a Control Register Writing or a Control Register Reading must be performed in order to avoid undesired behavior.
4.5
Using the Control Register String
The selected parameter values of the virtual ST7538 Control Register appear in the textbox at the bottom of the Control Register dialog box (Figure 10) in binary format from MSB to LSB. When the user modifies or clicks one of the Control Register parameters, the corresponding bits of the Control Register string become red. Figure 10. Write control register string and parameters position
CONTROL REGISTER STRING
Packet length Det. Method Watchdog (19-20) (12-13) (6) Sensitivity Output clock Det. Time Baud Rate (22) (15-16) (9-10) (3-4)
l
h
d
n
j
f
b
000100110010001010010111
m o k i g e c a
Carrier Frequency (0-2)
1
Packet en. Mains interface Tx Time Out (21) (14) (0-2) Packet mode Pre filter Zero Cross Deviation Baud rate (23) (11) (5) (17-18)
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Getting started
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4.6
Reading/Writing Control Register parameters
Figure 11 summarizes the Control Register reading/writing procedures with the PLM Demo Board. Figure 11. Control register writing/reading procedures
ST7538 CONTROL REGISTER WINDOW
3 1
1. Control Register Params Panel 2. WR Control Register String 3. Events Panel
2 4 5
6
4. Write CR Button 5. Read CR Button 6. Dual channel selection
On the Control Register window, click Write CTRL Register to transmit the 24-bit Control Register string to the ST7538 PLM Demo Board. Click Read CTRL Register to read the contents of the Control Register string. This displays the Read Control Register dialog box shown in Figure 12. Figure 12. Read CTRL Register dialog box
ST7538 READ CR WINDOW
1
If no communication issues occur, the Read Control Register string (which is similar to the Write Control Register string) displays the content of the ST7538 Control Register. Click the Read button in the Read Control Register dialog box to perform a new reading of Control Register string values. Click the Update Ctrl Panel button to update the Control Register parameter values with the 24 bits that are read. Click Close to close the Read Control Register dialog box.
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Transmission sessions
5
Transmission sessions
Click TX on the toolbar to open a transmission session and to display the Transmission Monitor dialog box shown in Figure 13. Figure 13. Transmission Monitor dialog box
ST7538 TRANSMISSION WINDOW
The textboxes display the content to be sent across the Mains in hexadecimal and ASCII format, respectively.
Transmission methods
Two methods of transmission are available: Sequence and Continuous. The Sequence method sends the content of textboxes across the Mains for selected number of times (Nr. parameter) with a delay of 200 ms between transmissions. It is important to note that each sequence transmitted is a single transmission session to ensure that no Timeout issues occur if the message to transmit is not too long. The Continuous method sends the content of the textboxes repeatedly across the Mains in a single transmission until the transmission is interrupted by the user or by a Timeout event. Note: A maximum of 127 bytes can be transmitted to the MCU.
Transmitting data
On EVALCOMMBOARD, the orange DL4 LED is turned on when a transmission begins. When a Timeout Event occurs, the red DL2 LED is turned on. On ST7538 EVAL 2.1 and 2.2, the red D9 LED is turned on when a transmission begins. When a Timeout Event occurs, the red D11 LED is turned on. Click ON to transmit the content of textboxes (that represents the data to be sent in both hexadecimal and ASCII format) across the Mains. Click Load File to load an ASCII or HEX text file in the textbox. Click Close to close the Transmission Monitor dialog box.
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Receive sessions
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6
Receive sessions
Click RX on the toolbar to open a receiving session and to display the Receive Monitor dialog box shown in Figure 14. Figure 14. Receive Monitor dialog box
ST7538 RECEPTION WINDOW
RX Textboxes (Hex and ASCII)
Frame synchronization controls
The textboxes display the content of the incoming data in hexadecimal and ASCII format, respectively. To clear the Hexadecimal and ASCII textboxes, click Reset Scope.
Frame synchronization and Header data
As it is not possible to know when the ST7538 starts to demodulate data incoming from the mains, a Frame Synchronization feature can be enabled in order to know when the data flow begins. If the Frame Synchronization feature is enabled (Frame Sync toggle switch), the data flow from the ST7538 is filtered from the MCU and the data is sent to the PC only when a header (defined by the Header parameter) is recognized. This ensures that all following bytes are correctly sent to PC if the transmitted message is preceded by a preamble (i.e. 0xAAAA or 0x5555) and by a header (i.e. 0x9B58). To mask the Header, enter the corresponding hexadecimal value in the Mask textbox. This feature enables the use of less than 16 bits or more than one header. The Masked Header textbox displays the masked header. The Data Bytes parameter selects how many bytes the MCU must transmit to the PC after a header recognition when in Frame Sync mode. If frame synchronization is not required, the user can switch OFF the Frame Sync feature and data are sent directly from the ST7538 to the PC. Note that since the first data demodulation time is unpredictable, byte synchronization is not ensured.
Receiving data
On EVALCOMMBOARD, the green DL3 LED is turned on in Receive mode. When a Carrier/Preamble is detected across the Mains, the yellow DL1 LED is turned on.
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Receive sessions On ST7538 EVAL 2.1 and 2.2, the green D12 LED is turned on in Receive mode. When a Carrier/Preamble is detected across the Mains, the yellow D10 LED is turned on. Two reception methods are available: Reception with synchronization or Reception without synchronization depending on the Frame Sync parameter setting. Click ON to start receiving data. Click Close to stop data reception.
Saving data
In order to save data received from the Mains in a text file (in either hexadecimal or ASCII format), click Save to File before clicking ON to start receiving incoming data. The maximum file size allowed is 64 KBytes. To stop saving data, click Stop Saving. Click Close to close the Receive Monitor dialog box.
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Ping sessions
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7
Ping sessions
In order to evaluate the reliability of a communication between two or more devices, a Ping session can be performed. A ping session consists of a Master that sends a sequence of messages to one or more Slaves. If the messages are correctly received by Slaves, they are re-sent to the Master enabling the application to collect a wide variety of statistical data. An error correction algorithm is also included. Click PING on the toolbar to open a Ping session. First select Master or Slave to set the device in the desired mode and to display the corresponding dialog box shown in Figure 15. Figure 15. Ping windows
ST7538 PING WINDOWS
R TE AS M
SL AV E
1
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Ping sessions
7.1
7.1.1
Opening a Ping Master session
Ping Master parameters
As shown in Figure 16, Table 18 following parameters can be selected for the Master device and the ping session. Figure 16. Ping Master dialog box
ST7538 PING MASTER WINDOW
MESSAGE SETTINGS
PING WAIT TIME & MSG NUMBER MEDIUM ACCESS CONTROL SETTINGS CURRENT MESSAGE INFORMATIONS EXECUTE/STOP BUTTONS
1
STATISTICAL INFORMATION
Table 18.
Ping master parameters
Description
Parameter Message settings Master address Nr. of slave addresses Nr. of messages
Defines the Address (from 1 to 255) of the Master device. Defines the Number (from 1 to 255) of Slave devices. Slave Addresses start from 1 to Nr. of Slave Addresses. Defines the total number of messages to send to Slave devices. The messages are numbered from 0 to Nr. of Messages. (Message "0" is used only to reset Slave statistical data). Repetition can be used to improve reliability of communication. When enable, if a message is not Acknowledged it is sent until three times before to consider it not Acknowledged.
Repetition control
Ping Wait Time and Message Number settings Defines the maximum wait time to obtain a valid response (with a valid address) from Slave device before considering not Acknowledged the message. The minimum value that can be selected depends on baud rate selected according the round trip time of message transmitted.(1) Defines the number of last message sent. It goes from 0 to Nr. of Messages and it is updated at every new message sent.
Wait time
Messages sent
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Ping sessions Table 18. Ping master parameters (continued)
Description
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Parameter Medium access control settings
Medium access control
Defines which type of medium access is used. Choices are "none", "BU" or "PD". In the two last settings, packets are sent only if respectively BU or CD/PD lines are not active. If "PD" is selected while "Carrier Detection" CR control is used, content of Control Register is changed in order to select the detection method to "Preamble detection". If BU or CD/PD lines are actives (depending on Medium Access Control selected), the Master waits for a time selected randomly between 4ms and 4*Max Wait Slot Nr. ms before to analyze if it is possible to transmit a packet. Defines the maximum time to wait when "BU" or "PD" Medium Access control are selected before to transmit the packet. When the Max Wait Time is elapsed, the packet is transmitted even if BU or CD/PD lines are actives.
Max wait slot nr.
Max wait time
Current message settings Shows information about the acknowledgement of the current message sent. Last Addressed Slave represents which Slave is the recipient of message. LEDs show if a message is acknowledged properly (OK), not correctly acknowledged (No Ack.), if the acknowledged message has errors corrected by FEC (Master used FEC) or if the acknowledged message has errors not corrected by FEC (Wrong FCS).
Current message status
Statistical data display These data are available for each Slave. Enter the name of the Slave device in Slave Description textbox. % OK messages: the total number of messages properly received plus those corrected through FEC Corrected messages: the number of messages corrected through FEC KO messages: the total number of messages with wrong FCS plus the number of message not acknowledged Wrong FCS messages: the number of messages with wrong FCS even after correction Not ACK messages: the number of messages not acknowledged Click Save Statistics to store collected data in a text file.
Statistical data for Slave
1. Minimum Wait time values are: @600 bps 300 ms, @1200 bps150 ms, @2400 bps75 ms, @4800 bps40 ms.
7.1.2
Starting a Master Ping session
Click Ping Start to start the ping session. The MCU on EVALCOMMBOARD continuously transmits the current status of every message transmitted to the PC. Click Ping Stop to end the ping session. Click Close to close the Ping Master dialog box.
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Ping sessions
7.2
7.2.1
Opening a Ping Slave session
Ping Slave parameters
As shown in Figure 17, Table 19 following parameters can be selected for the Slave device and the ping session. Figure 17. Ping slave window
ST7538 PING SLAVE WINDOW
SLAVE ADDRESS
MEDIUM ACCESS CONTROL SETTINGS
STATISTICAL INFORMATIONS
LAST RECEIVED MESSAGE INFORMATIONS EXECUTE / STOP / CLOSE BUTTONS
Table 19.
Ping slave parameters
Description
Parameter Slave address settings Slave address
Defines the Address (from 1 to 255) of Slave device.
Medium access control settings Defines which type of medium access is used. Choices are "none", "BU" or "PD". In the two last settings packets are sent only if respectively BU or CD/PD lines are not active. If "PD" is selected while "Carrier Detection" CR control is used, content of Control Register is changed in order to select the detection method to "Preamble detection". If BU or CD/PD lines are actives (depending on Medium Access Control selected), the Slave waits for a time selected randomly between 4ms and 4*Max Wait Slot Nr. ms before to analyze if it is possible to transmit a packet. Defines the maximum time to wait when "BU" or "PD" Medium Access control are selected before to transmit the packet. When the Max Wait Time is elapsed, the packet is transmitted even if BU or CD/PD lines are actives.
Medium Access Control
Max Wait Slot Nr.
Max Wait Time
Last received message information Last Received Message Shows the number of last message received. This field is updated only when Get statistical Data button is pressed.
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Ping sessions Table 19. Ping slave parameters (continued)
Description
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Parameter Statistical data display
The following statistical data are collected: OK messages: the total number of messages properly received plus those corrected through FEC Corrected messages: the number of messages corrected through FEC RX more than once: the number of messages received more than once KO messages: the number of message not received Wrong FCS messages: the number of messages with incorrect FCS even after correction Not RX messages: the number of message not received, calculated by subtracting the number of total message received (both the correct and the incorrect ones) from the number of last message received (Last Received Message field) Click Get Statistical Data to update statistical data. Click Save Statistics to store collected data in a text file.
7.2.2
Starting a Slave Ping session
Click Ping Start to start the ping session and enable the reception of data. Click Ping Stop to end the ping session. Click Close to close the Ping Slave dialog box.
7.3
Ping protocol
The Ping session consists of an exchange of packets between one Master device and one or more Slave devices. Figure 18 shows the ping message exchange format. Figure 18. Ping message format
ST7538 PING MESSAGE FORMAT
ORIGINAL MESSAGE (NOT CODED) Byte nr. Field 1 1 3 1 2
receiver Address
transmitter Address
Message number
repetition
FCS field
TRANSMITTED MESSAGE 22 bytes (CODED) Byte nr. Field 6
preamble+header
1
1
FEC
1
1
FEC
1
1
FEC
1
1
FEC
1
1
FEC
1
1
FEC
1
1
FEC
1
1
FEC
1
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Ping sessions When the user clicks PING START, the session begins and the Master sends a series of packets to one or more Slave devices. All the packets contain the following information:
Preamble (0xAAAAAAAA): 4 bytes Header (0x9B58 for Master packets and 0xE958 for Slave packets): 2 bytes
To improve reliability of communications, a FEC algorithm and one redundant byte is used for each of the following bytes of information:
Receiver Address: 1 byte (+ 1 byte for FEC) Transmitter Address: 1 byte (+ 1 byte for FEC) Current Message number: 3 bytes (+ 3 bytes for FEC) Repetition (0x00,0x01,0x02 if the same message has been transmitted once, two or three times): 1 byte (+ 1 byte for FEC) FCS field, obtained through a calculation of 12 previous bytes: 2 bytes (+ 2 byte for FEC)
The Slave detects, through the Receiver Address field, if the packet is headed for it or not. If the message is directed to it, a FCS operation is performed on 12 bytes following the preamble and the header. The result of calculation is compared with FCS field transmitted from Master. If the two values differ, an attempt of correction is executed (through FEC correction code) and a new comparison is performed. If the two FCS fields match, the message is considered OK from Slave and it is resent to the Master (inverting Master Address with Slave Address and recalculating FEC and FCS bytes). Otherwise, the message is considered KO and no response is performed. An exception occurs when Master transmits the message zero (with Message Number field 0x0 0 00). This message is used to reset the Slave, statistical data collected and no response to Master is needed. After a packet transmission, the Master waits (for a time defined in Wait Time in Master Window) the response from Slave, and if a message headed for it is detected it performs the same "correctness detection" operation above described in order to consider the message OK or KO.
Repetition function
To improve the reliability of communications, it is possible to use the repetition function. In this case, if a response is not detected by Master the packet is sent again for a maximum of three times before it is definitively considered Not Acknowledged.
Medium access control
A Medium Access Control is also implemented (for both Master and Slave) in order to prevent two or more devices from transmitting at the same time as described in Table 18 for the Ping Master parameters and Table 19 for Ping Slave parameters. Note: For a low-level description of Ping protocol, please refer to "Power Line Modem Evaluation FW".
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Ping sessions
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7.4
Ping session flowcharts
Figure 19 and Figure 20 describe the Master and the Slave loops, respectively, while a ping session is in progress.
Figure 19. Ping master loop
Ping Start SLAVE ADD = 1 MSG_NUM= 0 MSG_NUM 1
Create MSG (MSG_NUM)
Ping Master settings: ·MASTER ADDRESS ·SLAVE NUM ·TOT MESSAGE NUM YES
Create MSG (0)
MAC enable ? YES MAC enable ? NO MAC equal to PD and Control Register set to CD? NO YES Set Control Register to PD Message Acknowledged and Wait Time not elapsed? NO Transmit MSG (MSG_NUM) Wait RAND time (from 1 to Max Wait Slot No. * 4 ms)
·WAIT TIME ·MAC (MEDIUM ACCESS CONTROL) ·MAX WAIT SLOT NR. ·MAX WAIT TIME ·REPETITION NO Line busy and Max Wait Time not elapsed? YES
NO Transmit MSG (0)
Ping Master current message output data: ·OK MESS. ·CORR. MESS. ·KO MESS.
YES
Slave add. 1
Repetition enabled and < 3 messages transmitted? NO
NO
Line busy and Max Wait Time not elapsed? YES Wait RAND time (from 1 to Max Wait Slot No. * 4 ms) NO
YES
Repetition enabled and < 3 messages transmitted?
YES
·WRONG FCS MESS. ·NOT ACK MESS.
Master Address correct ?
NO
YES
Slave Add. < Slave No.?
YES Calculate FCS
NO YES MSG_NUM < TOT MSG NUM? FCS NO calculated equal to FCS received? YES
NO Ping Stop
Use FEC and calculate a new FCS
New FCS equal to FCS of corrected message? YES SLAVE ADD 1 OK MESS. CORR MESS.
NO
WRONG FCS MESS.
MSG NOT ACK
YES Slave Add. < Slave No.?
NO
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Ping start
Ping sessions
TOT RX MSG = 0 TOT OK MSG = 0 TOT CORR MSG = 0 TOT RX MORE MSG = 0 TOT WR FCS MSG = 0
Ping Slave settings: FCS NO calculated equal to FCS received? · SLAVE ADDRESS Use FEC and calculate a new FCS · MAC (MEDIUM ACCESS CONTROL) MAX WAIT SLOT NR. MAX WAIT TIME Ping Slave Total Message Data:
YES
Message detected ?
NO
New FCS equal to FCS of corrected message?
NO
· LAST MSG REC. · TOT OK MSG · TOT CORR MSG
YES
YES
· TOT RX MORE MSG · TOT WR FCS MSG
SLAVE ADDRESS correct?
NO
Message already received?
YES
YES
Message already received? NO
YES
NO YES TOT OK MSG 1 TOT RX MORE MSG 1
TOT CORR MSG 1
TOT WR FCS MSG 1
MSG number = 0 ? Get LAST MSG REC and create reply message
NO Calculate FCS
YES MAC enable ?
NO Transmit message
MAC equal to PD and Control Register set to CD? NO Wait RAND time (from 1 to Max Wait Slot No. * 4 ms)
YES Set Control Register to PD
NO
Line busy and Max Wait Time not elapsed? YES
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Communication session examples
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8
Communication session examples
This sections provides examples of some of the most common operations that can be performed with two or more Demo Boards. The operations performed are: Communication session without Frame Synchronization Communication session with Software Frame Synchronization Ping session
8.1
8.1.1
Setup procedure
Required hardware
The following hardware is required for these example sessions: Two EVALCOMMBOARD rev. 1.1 + EVALST7538DUAL rev. 3.1 (72/86 kHz) One PC with two RS-232 ports
8.1.2
Hardware setup
The setup of the communication sessions is common for all tests. 1. Connect the PLM Demo Boards to the EVALCOMMBOARDs. 2. Connect the boards to the two RS-232 PC ports through the serial cables to the PC. 3. Link the PLM Boards to an isolated 110/220V~ Mains voltage. 4. Finally, reset the two EVALCOMMBOARDs by pressing the Reset button.
8.1.3
Software setup
To control two devices at the same time, the user must run two sessions of the program: 1. 2. Open Start, Programs, ST7538_40 FSK Power Line Modem Demo Kit and click ST7538_40 FSK Power Line Modem Demo Kit. Then, select the correspondent COM available for every session (in this example COM1 for the first board and COM3 for the second board); enabling the GUI to communicate with each EVAL Board.
Figure 21. Communication setup: COM selection
COM port selection TOOLBAR enabled
STATUS BAR update
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Communication session examples After selecting COM port, the Status Bar is updated showing information about the selected COM port, SW/FW revisions and the Link status. Before starting a Communication session, the user must perform a Write Control Register for the two windows. 3. 4. Click REG on the toolbar to open the Control Register dialog box. Ensure that the Dual Channel feature is enabled and select 72 kHz for the first channel (CH1) and 86 kHz for the second channel (CH2).
Note:
In these Dual Channel sessions, the first channel is used so the CH1 is selected (through the binary control below the checkbox). 5. 6. Because only few bits change for the sessions in respect to the default Control Register parameters, click Read CTRL Register and then Update CTRL Panel. Set the Carrier Frequency to 72 kHz and the Detection Method to Preamble to ensure that the incoming data are received only when a preamble is detected across the Mains.
Now, the two Control Register dialog boxes should appear as shown in Figure 22. Figure 22. Control Register dialog boxes after setup
COM 1
COM 3
Once the Control Registers are correctly configured, communication can begin between the boards.
8.2
Communication session without Frame Synchronization
In this example, the board connected to COM1 is used as the Transmitter while the board connected to COM3 is used as the Receiver. Five messages are transmitted across the Mains and the receiving method is not synchronized, so incoming data from ST7538 are sent directly to the PC. Actions to perform on GUI connected with COM3: 1. 2. 3. Click Rx on toolbar to open the Rx Monitor dialog box. Set FRAME SYNC to OFF. Click ON.
Now the receiving board is waiting incoming data. (It activates itself only when a preamble is detected across the Mains).
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Communication session examples Actions to perform on GUI connected with COM1: 1. 2. 3. 4. 5. Click Tx on toolbar to open the Tx Monitor dialog box. Write the preamble "AAAAAAAA" in the hexadecimal textbox.
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Add the text string "transmission without synchronization" in the ASCII textbox. Select Sequence Mode and set Nr. to "5". Click ON.
Five messages are sent with a temporal distance of 200 milliseconds. Figure 23. Communication without Frame Synchronization example
SynchSonczeonmed sage r yni hr d izes
In Figure 23 (COM3 section), the five transmitted sequences do not appear to be received correctly. This behavior is due to fact that the ST7538 starts writing data on the RX line at different time for every message, because in Synchronous Mode the PLL that provides the CLR/T signal must reach the lock-in condition. Lock-in condition can only be reached after an undetermined number of demodulated data transitions (maximum 5) and during this time one or more bits can be lost. For this reason, if a sequence of bits that starts like: "1010-1010-1010-1010-...." (0xAAAA... in hexadecimal) is transmitted, the receiver can only demodulate with correct timings a part of this sequence. For example, if the first "10101" is lost, the PC will receive the sequence "0101-0101010. . ." (or 0x55 in hexadecimal). So, even if all bits are correct, byte synchronization is lost. Figure 24 shows an example of timing diagram for a baud rate of 2400.
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Communication session examples Figure 24. Demodulation timings for RX with preamble detection (@2400 baud)
bit time (0.417ms)
DATA DEMOD. INTERNAL SIGNALS PLL LOCK-IN
010101010
PLL lock-in (variable) preamble detected CD/PD detection time (1ms)
CD/PD EXTERNAL SIGNALS RxD RxD NOT ACTIVE RxD ACTIVE
0
1
0
8.3
Communication session with Frame Synchronization
In this example, the board connected to COM1 is the Transmitter while the board connected to COM3 is the Receiver. Five messages are transmitted across the Mains and the receiving method includes Frame Synchronization, so incoming data from ST7538 are supervised by the microcontroller on EVALCOMMBOARD and only the bits that follow the sequence "0x9B58" ("1001-10110101-1000") are sent to the PC. Actions to perform on GUI connected with COM3: 1. 2. 3. 4. 5. 1. 2. 3. 4. 5. 6. Click Rx on toolbar to open the Rx Monitor dialog box. Set FRAME SYNC to ON. Write "9B58" in Header textbox and "FFFF" in Mask textbox. Set Data Bytes to "36" Click ON. Click Tx on toolbar to open the Tx Monitor dialog box. Write the preamble "AAAAAAAA" in the hexadecimal textbox. Add the header "9B58" in the hexadecimal textbox. Add the text string "transmission with SW synchronization" (length = 36 bytes) in the ASCII textbox. Select Sequence Mode and set Nr. to "5". Click ON.
Actions to perform on GUI connected with COM1:
Five messages are transmitted. Using the Frame Synchronization feature, the user ensures that the transmitted bytes always arrive synchronized to the PC as shown in Figure 25.
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Communication session examples Figure 25. Communication with Frame Synchronization example
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COM 1
CO M 3
FRAME Header (0x9B58)
8.4
Ping session
In this example, the board connected to COM1 is the Master while the board connected to COM3 is the Slave. 100 messages are exchanged from Master to Slave and statistical data (as for Master as for Slave) are saved in two text files. Actions to perform on GUI connected with COM3: 1. 2. 3. 4. 5. 6. 1. 2. 3. 4. 5. 6. 7. Click PING on toolbar to open the Ping dialog box. Select Slave and click OK. Set Slave Address to "1". Write "Ping session nr. 1" in Slave Description field. Set Medium Access Control to "PD", Max Wait Slot Nr. to "10" and Max Wait Time [ms] to "1000". Click Ping Start. Click PING on toolbar to open the Ping dialog box. Select Master and click OK. Set Master Address and Nr. of Slave Addresses to "1". Set Nr. of Messages to "100" and Repetition Control to "3". Set Wait Time [ms] to "255". Set Medium Access Control to "PD", Max Wait Slot Nr. to "10" and Max Wait Time [ms] to "1000" Click Ping Start to start the ping session.
Actions to perform on GUI connected with COM1:
Saving statistics
When all messages are transmitted, on the Ping Master dialog box click Save Statistics and selecting the path and the name of the text file (in this case "Ping session nr. 1 (Master).txt").
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Communication session examples To save Slave statistics, click Get Statistical Data (to update the statistics), click Save Statistics and selecting the path and the name of the text file (in this case "Ping session nr. 1 (Slave).txt"). Figure 26. Ping master session and save statistics
Figure 27. Ping slave session and save statistics
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Revision history
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9
Revision history
Table 20.
Date 24-Jul-2006
Revision history
Revision 1 Initial release Changes
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