ModMaster Manual v3.15 - 7.3.  Register value tracing

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7.3.  Register value tracing

To enable tracing of register reads, select the TracingTrace values read checkbox.

To enable tracing of register writes, select the TracingTrace value written checkbox.

If tracing is enabled, each read or write of a defined register (see Registers and File Registers) is traced as a single line in the log. Each line begins with the time of the read or write. The time is followed by the character 'R' for a register read or 'W' for a register write. This is followed by the slave ID, the register address and the value read or written. For example (with message tracing also enabled):

17:41:12.272: < transid 8 slave 1 pdulen 5 func 3: 00 11 00 03
17:41:12.273:       Request: Read Holding Registers: address 17, count 3
17:41:12.276: > transid 8 slave 1 pdulen 14 func 3: 0c 00 00 00 1d 00 00 01 55 41 ...
17:41:12.277:       Response: Read Holding Registers: byte count 12, data bytes 12
17:41:12.281:         R  1  17  29
17:41:12.282:         R  1  18  341
17:41:12.284:         R  1  19  29.230000

The register address for ordinary registers is a "model" address (see Address mapping). The register address for a file register consists of the file number and register number separated by ':'. For example (with message tracing also enabled):

17:37:08.552: < transid 6 slave 1 pdulen 16 func 20: 0e 06 00 03 00 03 00 03 06 27 ...
17:37:08.553:       Request: Read File Record
17:37:08.557: > transid 6 slave 1 pdulen 16 func 20: 0e 07 06 85 2b 00 24 03 75 05 ...
17:37:08.558:       Response: Read File Record
17:37:08.565:         R  1  3:3  34091
17:37:08.567:         R  1  3:4  36
17:37:08.568:         R  1  3:5  885
17:37:08.569:         R  1  10000:102  4486
17:37:08.570:         R  1  10000:103  20371