MPC5200 mscan timing parameters

albrechtmoll — Fri, 17 Apr 2015 12:38:50 GMT

We are trying to evaluate MPC5200B for SAE J1939-14 (500 kBit/s) which poses requirements for bit processing time. I did not find any AC timing parameters (e.g. for loss of arbitration) for mscan. Where can I find these?

Our design also employs galvanic isolation with additional propagation delays.

For your understanding: SAE J1939-14 states:

5.4 Time Delay

The total delay allowed for the ECU is 390 ns. This is the sum of all of the following delays:

Bus input signal to transceiver RXD logic output

CAN controller logic processing

Transceiver TXD logic input to bus output signal

Common mode choke or other filtering components

We need numbers on 'CAN controller logic processing'

Re: MPC5200 mscan timing parameters

albrechtmoll — Fri, 01 May 2015 11:02:41 GMT

I had opened a Service Request for this at freescale and had a very intensive email dispute with them.

We exchanged references to application notes of TI, Analog Devices and even one of freeescale ;-). Most of them covered can parameter calculation only, none contained the requested timing numbers on the MPC5200B CAN.

By now I think I (and my freescale support guy) have a broad overview of existing application notes on CAN timing of other manufacturers, insight in controller timing characterization from the original Bosch CAN specification. From what I heard from freescale during this support request I reckon they have no timing parameters on this. For me this attempt was a dead-end flop, taking me much time.

So for the next steps I have to stick to the AD statement "The CAN controller I/O is not a major contributor, and can often be ignored" ("... , but a thorough assessment will allow for it.") and the TI statement "depends on the selected components: CAN controller (50 ns to 75 ns)..." if I do not want to characterize the MPC5200 myself.

topic Re: MPC5200 mscan timing parameters in MPC5xxx

MPC5200 mscan timing parameters

Re: MPC5200 mscan timing parameters