![](http://datasheet.mmic.net.cn/110000/M32186F8VFP_datasheet_3496152/M32186F8VFP_693.png)
13
CAN MODULE
13-83
32185/32186 Group Hardware Manual
Rev.1.10 REJ09B0235-0110 May 15, 07
Notes: If a transmit request is written to this register while the CAN module is reset (CAN0CNT/
CAN1CNT FRST or RST bit = "1"), it starts sending upon detecting 11 consecutive recessive
bits on the CAN bus after exiting the reset state.
If data/remote frame transmit requests are issued for two or more slots, the slot with the small-
est slot number sends a frame. If data/remote frame receive requests are issued for two or
more slots, the slot with the smallest slot number among the slots satisfying the receive condi-
tion receives a frame.
If transmission failed when single-shot mode is selected, this register is cleared to H’00.
(1) TR (Transmit Request) bit (Bits 0, 8)
To use the message slot as a transmit slot, set this bit to "1." To use the message slot as a data frame or
remote frame receive slot, set this bit to "0."
(2) RR (Receive Request) bit (Bits 1, 9)
To use the message slot as a receive slot, set this bit to "1." To use the message slot as a data frame or
remote frame transmit slot, set this bit to "0."
If TR (Transmit Request) bit and RR (Receive Request) bit both are set to "1," device operation is unde-
fined.
(3) RM (Remote) bit (Bits 2, 10)
To handle remote frames in the message slot, set this bit to "1." There are following two methods of settings
to handle remote frames:
Set for remote frame transmission
The data set in the message slot is transmitted as a remote frame. When the CAN module finished
sending, the slot automatically changes to a data frame receive slot. However, if a data frame is
received before the CAN module finished sending a remote frame, the received data is stored in the
message slot and the remote frame is not transmitted.
Set for remote frame reception
Remote frames are received. The processing to be performed after receiving a remote frame is
selected by RL (automatic response inhibit) bit.
(4) RL (Automatic Response Inhibit) bit (Bits 3, 11)
This bit is effective when the message slot has been set as a remote frame receive slot. It selects the
processing to be performed after receiving a remote frame. If this bit is set to "0," the message slot automati-
cally changes to a transmit slot after receiving a remote frame and transmits the data set in it as a data
frame. If this bit is set to "1," the message slot stops operating after receiving a remote frame.
Note: Always set this bit to "0" unless the message slot is set for remote frame reception.
13.2 CAN Module Related Registers