TMS570LS1227: DCAN receive missing frames

marc bunyard said:

If I transmit the messages slowly they are received reliably,

Do you mean the lower baudrate, or large period of time between frames? 

Are the 2nd and 3rd mailboxes configured to have the correct message ID for example 2 or 3? 

QJ Wang said:

Do you mean the lower baudrate, or large period of time between frames? 

Are the 2nd and 3rd mailboxes configured to have the correct message ID for example 2 or 3? 

When there is a Larger period between frames, e.g a few milliseconds all 3 messages are all received, newdat bits are set as expected.  However the  current sensor transmits with about 0.2uS between each of the three frames.

Yes the second and third mailboxes are configured with correct ID and absolute mask (0x7ff)

The baudrate is 500k

Thanks for getting back to me

marc bunyard said:

I need to receive data from a current sensor which transmits 3 frames every 20mS, they are on sequential canIDs with 0.2mS between each frame.

A CAN frame with 8 bytes payload takes around 2us*112bits = 0.224ms. I don't think any problem to read the received data from the mailboxes in 20ms. 

Using IF3x and DMA is easier to transfer data from mailbox to SRAM.

I agree, it shouldn't be a problem, however in our tests the dcan module appears to fail to receive the third of the three messages when they are transmitted by the current sensor.

Here's the messages we are trying to receive

ID: 0x521  cycle time: 20mS

ID: 0x522  cycle time: 20mS

ID: 0x523  cycle time: 20mS

Is there an example if how to use IF3x and DMA? we are using the code gnereated by halcogen at the moment.

Please refer to this thread for IF3x and DMA:

https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers/f/arm-based-microcontrollers-forum/981103/tms570ls1114-can-function-issue/3626130?tisearch=e2e-sitesearch&keymatch=IF3x%252525252520AND%252525252520DMA#3626130