Negative Response Codes

[sonofsmog]

Is it possible to return negative response codes (ISO-1420, CAN) with the stock software/firmware or would we need to modify it?

[stanley]

some PIDs can have negative value.

[sonofsmog]

I mean negative response codes. Not negative values. Services can report that they are not supported, not ready, response pending, etc.

The negative response Service is $7F.

So for example if a scan tool is requesting say the CVN (Sevice 0x09, InfoType 0x06.) The vehicle could respond something like $7F $09 $18.

$7F being the negative response SERVICE
$09 being the requested service
$18 being the reason.

Does the emulator support this?