32186 datasheet(693/1032 Pages) RENESAS

693 / 1032 page

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

32186 Datasheet(PDF) 693 Page - Renesas Technology Corp