1997 F-Body ECM

[kur4o]

I think obdx cable is a true hex with emulated elm compatability. WHich means you can configure it to send a message the way you want it.

Maybe some 2-3 bytes header to specify message length and some instruction byte???

Also as far as I know all cables handle the crc byte on hardware level. Maybe there is some settings that can show the crc onincoming on sure on outgoing messages.

I guess your cable is transparent and arduino is just a gateway for communication.

The elm comm speed can be easily reconfigured on boot up. Most are set to 38000 or 115000 as a default. You can make it user configurable or crawiling an ATZ message on different bauds till you get a response.

[sherlock9c1]

Doublecheck me. I think the correct DVI format for an example ELM message is:

ELM: DX SD 4C 10 F0 23 00 0E 00

DVI: 10 XX 4C 10 F0 23 00 0E 00 YY where XX is message length, and YY is checksum.

So the message length XX would be 07;

and YY = 0x194; inverse = FFF-194 = E6B, so YY = 6B.

Thus, DVI message is 10 07 4C 10 F0 23 00 0E 00 6B

Am I doing this right?