MCAN_TXBRP

MCAN Transmit Buffer Request Pending

MCAN_TXBRP bits which are set while a Tx scan is in progress are not considered during this particular Tx scan. In case a cancellation is requested for such a Tx Buffer, this Add Request is cancelled immediately, the corresponding MCAN_TXBRP bit is reset.
  0xCC 32 Read-only 0x00000000  
Parent topic: Register Summary

MCAN Transmit Buffer Request Pending

Bit  31 30 29 28 27 26 25 24  
  TRP31 TRP30 TRP29 TRP28 TRP27 TRP26 TRP25 TRP24  
Access  R R R R R R R R  
Reset  0 0 0 0 0 0 0 0  
Bit  23 22 21 20 19 18 17 16  
  TRP23 TRP22 TRP21 TRP20 TRP19 TRP18 TRP17 TRP16  
Access  R R R R R R R R  
Reset  0 0 0 0 0 0 0 0  
Bit  15 14 13 12 11 10 9 8  
  TRP15 TRP14 TRP13 TRP12 TRP11 TRP10 TRP9 TRP8  
Access  R R R R R R R R  
Reset  0 0 0 0 0 0 0 0  
Bit  7 6 5 4 3 2 1 0  
  TRP7 TRP6 TRP5 TRP4 TRP3 TRP2 TRP1 TRP0  
Access  R R R R R R R R  
Reset  0 0 0 0 0 0 0 0  

Bits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 – TRPx: Transmission Request Pending for Buffer x

Transmission Request Pending for Buffer x

Each Tx Buffer has its own Transmission Request Pending bit. The bits are set via register MCAN_TXBAR. The bits are reset after a requested transmission has completed or has been cancelled via register MCAN_TXBCR.

TXBRP bits are set only for those Tx Buffers configured via MCAN_TXBC. After a MCAN_TXBRP bit has been set, a Tx scan (see Tx Handling) is started to check for the pending Tx request with the highest priority (Tx Buffer with lowest Message ID).

A cancellation request resets the corresponding transmission request pending bit of register MCAN_TXBRP. In case a transmission has already been started when a cancellation is requested, this is done at the end of the transmission, regardless whether the transmission was successful or not. The cancellation request bits are reset directly after the corresponding TXBRP bit has been reset.

After a cancellation has been requested, a finished cancellation is signalled via MCAN_TXBCF.

• after successful transmission together with the corresponding MCAN_TXBTO bit.

• when the transmission has not yet been started at the point of cancellation.

• when the transmission has been aborted due to lost arbitration.

• when an error occurred during frame transmission.

In DAR mode, all transmissions are automatically cancelled if they are not successful. The corresponding MCAN_TXBCF bit is set for all unsuccessful transmissions.

ValueDescription
0

No transmission request pending
1

Transmission request pending