MSM9225B User’s Manual
Chapter 2 Register Descriptions
2 – 33
2.4.9 Standby Control Register (STBY: 8Ehex)
This register is used for setting the stop mode and the sleep mode.
A “0” is read after the stop or sleep mode is terminated.
The bit configuration is as follows:
MSB
Not
used
Not
used
Not
used
Not
used
Not
used
Not
used
SLEEP STOP
LSB
STBY (8Ehex), R/W: R/W
Initial
value:
0
0
0
0
0
0
0
0
0
Normal operation
1
Set stop mode
0
Normal operation
1
Set sleep mode
Unused bit.
Write a “0”.
Note:
A “0” is read out after the sleep mode or the stop mode is terminated.
Figure 2-32 Standby Control Register (STBY)
(1) Stop mode: STOP
If STOP is set to “1”, the MSM9225B will enter the stop mode when the CAN bus is idle.
In stop mode, the contents of the message memory and control registers are held but the oscillator and
all circuits stop to save power consumption. Access to/from external units is therefore disabled.
Stop mode is terminated by a reset signal input from the
RESET
pin or a “L” level input to the
CS
pin.
At reset, STOP is set to “0”.
(2) Sleep mode: SLEEP
If SLEEP is set to “1”, the MSM9225B will enter the sleep mode when the CAN bus is idle.
In sleep mode, the contents of the message memory and control registers are held and the differential
input of Rx0 and Rx1 operates, but the oscillator and other circuits stop operation. Access to/from
external units is therefore disabled.
Sleep mode is terminated by a reset signal input from the
RESET
pin or a “L” level input to the
CS
pin,
or by the differential input of Rx0 and Rx1.
When both stop mode and sleep mode are set at the same time, the MSM9225B enters stop mode.
At reset, SLEEP is set to “0”.
Summary of Contents for MSM9225B
Page 7: ...Chapter 1 Overview...
Page 13: ...Chapter 2 Register Descriptions...
Page 53: ...Chapter 3 Operational Description...
Page 62: ...Chapter 4 Microcontroller Interface...
Page 71: ...Chapter 5 Electrical Characteristics...
Page 81: ...Appendixes...