Table of Contents
Advertisement
CHAPTER 16 CAN controller
G
Setting of transmission request
To set a transmission request, set the TREQx bit in the transmission request register to "1".
G
Canceling transmission request
• To cancel the transmission request held in the message buffer (x), write 1 to the TCANx bit in the
transmission cancel register.
• When the TREQx bit is "0", transmission cancel is terminated or transmission is completed.After that,
check the TCx bit in the transmission complete register (TCR). If the TCx bit is 0, transmission cancel is
terminated and if the TCx bit is "1", transmission is completed.
G
Processing when transmission completed
• When transmission is successful, "1" is set to the TCx bit in the transmit complete register (TCR).
• When a transmission complete interrupt is enabled (TIER: TIEx = "1"), an interrupt is generated.
• After checking the completion of transmission, write "0" to the TCx bit in the transmission complete
register (TCR) to clear the transmission complete register (TCR).When the transmission complete
register (TCR) is cleared, the transmission complete interrupt is cancelled.
• When the message is received or stored, the held transmission requests are cancelled as follows:
- When a data frame is received, the request to transmit a data frame is cancelled.
- When a data frame is received, the request to transmit a remote frame is cancelled.
- When a remote frame is received, the request to transmit a remote frame is cancelled.
When a remote frame is received or stored, the request to transmit a data frame is not cancelled but the data
in the ID register and DLC register are rewritten to the data of the received remote frame.Therefore, the
data in the ID register and DLC register for the data frame to be transmitted are replaced by data in the
received remote frame.
546
Advertisement
Table of Contents
