Fujitsu FR81S User Manual
CHAPTER 41: CAN
4. Registers
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER
: CAN
FUJITSU SEMICONDUCTOR CONFIDENTIAL
18
[bit2]: Status interrupt code enable bit
SIE
Function
0
Disables the interrupt code setting to the CAN interrupt register (INTR) with the bit
change for TxOk, RxOk or LEC of the CAN status register (STATR).
[Initial value]
1
Enables the status interrupt code setting to the CAN interrupt register (INTR) with the
bit change for TxOk, RxOk or LEC of the CAN status register (STATR). The bit change
for TxOk, RxOk and LEC generated by the writing from the CPU is not set to the CAN
interrupt register (INTR).
[bit1]: Interrupt enable bit
IE
Function
0
Disables interrupt. [Initial value]
1
Enables interrupt.
[bit0]: Initialization bit
Init
Function
0
Operates after the initialization release of the CAN controller.
1
Initialize the CAN controller and stops the operation.
[Initial value]
Notes:
⋅
The bus-off recovery sequence cannot be shortened with the Init bit setting/release. When a device is
in the bus-off state, the CAN controller itself sets "1" to the Init bit and stops all bus operations. When
the Init bit is cleared to "0" in the bus-off state, the bus operation is stopped until the bus-idle
continues 129 times (11-bit recessive is regarded as one time). The error counter is reset after the
execution of the bus-off recovery sequence.
⋅
When the Init bit is set to "1" and then to "0" during the bus-off recovery sequence, the bus-off
recovery sequence runs from the beginning (129 times regarding 11-bit recessive as one time).
⋅
To set the CAN bit timing register (BTR), set "1" to the Init and CCE bits.
⋅
When "1" is set to the Init bit during transmission/reception, the transmission/reception is stopped
immediately.
⋅
Before transiting to the low-power consumption mode, set "1" to the Init bit and initialize the CAN
controller.
⋅
To change the clock divide ratio which supplies to the CAN interface by the following registers, set
"1" to the Init bit and stop the CAN controller.
⋅
CAN bit timing register (BTR)
⋅
CAN prescaler extension register (BRPER)
⋅
CAN prescaler register (CANPRE)
MB91520 Series
MN705-00010-1v0-E
1711