Timing Parameters¶
UDS timing parameters control how quickly requests and responses occur.
| Parameter | Typical Value | Meaning |
|---|---|---|
| P2Server_max | 50 ms | Normal response time limit |
| P2*Server_max | 5000 ms | Extended response time after RCRRP |
| S3Client | 5000 ms | Session keep-alive interval |
| P3Client_physical | 2000 ms | Inter-message timing |
Why timing matters¶
If you violate timing requirements, ECUs may return NRC 0x21 (busyRepeatRequest) or 0x78 (responsePending).
pyudskit behavior¶
pyudskit surfaces these values in the system prompt to improve LLM reasoning and can be used in flow explanations.