Legacy RxFIFO HR Timestamp

[anakha]

Hi,

I am having issue with reading timestamp for Legacy Rx FIFO buffers. only 8 Rx Buffer is defined (from 0 to 7) and 8th and 9th are defined as normal MB.

I can read normal MB timestamps. such as HR_TIMESTAMP[8] as shown in yellow, updates each cycle but [3] is not changes. It display random constant number. 

You can also see ID_HIT is 3, which means 3rd CAN msg ID defined in RX Buffer hits, right?

anakha_2-1721650176802.png

FlexCAN is configured as below. STM0 Ch 0 is set for HR timer it runs without problem. (otherwise HR[8] and HR[9] cannot be read.

anakha_1-1721649888254.png

I also found below definition in RM but I have no idea what that means.

What does " the message buffers should be unlocked within each 20 CAN bits" mean?

anakha_0-1721649794651.png

It is also mentioned that reading timestamp unlocks MB as written in 73.3.4 of RM at 5th item.

anakha_3-1721650738788.png

so, how can I read HR time stamp, any suggestion?

thanks in advance

regards

[Senlent]

Hi@anakha

Could you please provided your test demo, i may need some time to test it, it's also a new feature to me.