MembersPage/GasEngine/AutoDerivativeSmallGasEngine/ModbusSlave

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Special fw built with modbus slave on 2nd RS232

Example communication, ECU = modbus slave


2nd RS232 hardware for CRC protected special commands, voltage measured from pin5 (GND) base

1st RS232 (standard):

2nd RS232: (as requested for assembled VEMS ECU )


Modbus Write:

Examples:

(02) 06 00 XX VV 00 (CRC CRC)

XX table:


Modbus read (subset or all) runtime vars command

Standard modbus command 03 (Read holding registers) example:

(02) 03 00 XX 00 LL (CRC) XX = index, LL = length in words (max 38)

  • response is 2*LL bytes (as in modbus standard), from 2*XX byteoffset. The full set of runtime variables can be read in 1 or multiple queries.

Register/Address for reading

Eg XX=07 and LL=01

Byte offsets (for some important values):

See <VT installdir> /config/vemsTune-v3-1.2.23.ini

Other:

- EGT1, EGT2

- worst knock value

- relative knock values 0..7

- errors, trigger error (hibák)

- individual power (gyújtás kihagyás)


Firmware version and old config

# Version: 1.2.24
# SerialNumber: v3.3_u008792
# SerialNumber Raw: 76 33 2E 33 5F 75 30 30 38 37 39 32 
# CompilationTime: 2014-03-13 09:23
# Signature: VEMS v1.2.24 16x14 kpa=2,2
# CompileOptions: 000000DE (woodgas option?)

Files: