Corvette CCM Reverse Engineering Anyone?

[NomakeWan]

kur4o brings up a good point; the other problem is that my documentation from '89 that covers the '90 model lists $41 as being 61 for length, while our 94~95 cars are 67. So there's clearly more data in the regular poll response than before, and that brings up the excellent question of what all that extra data is. Rats.

As for idle data, here's key-on-engine-off data you can inject if you want to pretend to be the PCM and respond to 4057FFFF6B:

416702F6006F580100782010880052FFFF5AA0A07E

EDIT: And thanks to kur4o's above post, here's the layout for that poll response. I'm only missing the definitions for four sections ("tcnt?" and the two "A0" bytes), and of course the breakdown of what all the bits in the two Status/Option bytes represent.

41 ECM to CCM Poll Response
67 Message Length
02 RPM (45 RPM appears to be as low as it goes on $EE)
F6 MAP
00 TPS
6F CTS
58 IAT
01 Status Byte 1
00 Status Byte 2?
78 Engine Revolutions
20 Injector On Time (Byte 1)
10 Injector On Time (Byte 2)
88 Injector Scaler
00 VSS
52 Oil Temp
FF ?
FF ?
5A Auto Trans Temp
A0 ?
A0 ?
7E Checksum