Hi,
I'm currently investigating about the impact of the samplepoint (SP) to the CAN-buslength with 1Mbit baudrate because we can see some errorframes in our machine.
On my desk I have a simple CAN-Network with 3 CAN-controllers:
2x Tms320LF2407 and 1x SJA1000 and lots of pieces of cable.In the past we set the controllers with 60% SP in TMS320LF2407 and 75% SP in SJA1000. To improve the cablelength, I tried to increase the SP in TI, which worked out like expected. I played around with the SP in both controllers (TABLE1) and found an ideal setup with 87% for TI and 75-80% for SJA1000. If I did not made any mistake in the calculation (I checked it twice) I find it a quite strange result!
Does anybody can explain such a behaviour?
Regards,
Wolfgang Kopp
TABLE1 reached cable length without errorframe at high busload:
SJA_SP 75% 80% 87% TI_SP 60% 10m 73% 18,8m 20,6m 80% 24,4m 22,4m 17m 87% 28,1m 28,1m 18,8m