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Old 09-02-2010, 05:03 AM   #586 (permalink)
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yes, ISO is slow But acceptable

6bytes request (3header, 2payload, 1crc) = 4.6ms (10400speed limit)

10ms delay after each byte in Obduino32K code (function iso_write_byte). 6x10 = 60ms

ECU responds after 25ms

response is 7-10 bytes (avg 8bytes) = 6.2ms

Mandatory delay before next request 55ms

so we have 151ms in total, or 6.6pids/sec physical limit.
+ Obduino32K code is also working + LCD commands are also not so fast.

Tested PID_SEC pid in my car - and i get 7, so calculations looks good

according to page 7
there should be at least 5ms delay before each byte. it would be no big increase, but still - increase 6.6p/s -> 8.2p/s

Last edited by eimix; 09-02-2010 at 05:26 AM..
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