CAN BUS OBD2 4 Byte messages

Products & Technology Shields
#1

I’m trying to get the CAN shield to send long (but not extended 29 bit) answers but I’m striking out… Everything else works and communicates properly.



Here’s the relevant code:

[code]

// Tell the reader what PIDs we support
// Service 01 PIDs supported 01-20 - Set to DEC 24 59 80 00 = HEX 18 3B 50 00
// PID 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
// Status 0 0 0 1 1 0 0 0 0 0 1 1 1 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
if(BuildMessage==“2,1,0,0,0,0,0,0,”) {unsigned char s0pid020[8] = {4, 65, 00, 24, 59, 80, 00}; CAN.sendMsgBuf(0x7E8, 0, 8, s0pid020);}

[/code]

I’m plugged directly into it with a ELM based scan tool and sending 0100 returns:

ATSP0

OK



0100

41 00 18 3B



Containing only the “18 3B” instead of the full “18 3B 50 00” response that a diagnostic tool would expect. I’m sure it’s just something simple and stupid but I’ve read everything I can think of and can’t find a useful solution. Thanks!

#2

Hello,

I want to know why do you define an 8-sized array with 7 elements？
</s>unsigned char s0pid020[8] = {4, 65, 00, 24, 59, 80, 00}<e>