s908gz60cfa Freescale Semiconductor, Inc, s908gz60cfa Datasheet - Page 145

• Manufacturer Part Number: s908gz60cfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

12.8.1 MSCAN08 Sleep Mode
The CPU can request the MSCAN08 to enter the low-power mode by asserting the SLPRQ bit in the
module configuration register (see
depends on its activity:
Freescale Semiconductor
•
•
•
If it is transmitting, it continues to transmit until there is no more message to be transmitted, and
then goes into sleep mode
If it is receiving, it waits for the end of this message and then goes into sleep mode
If it is neither transmitting or receiving, it will immediately go into sleep mode
1. ‘X’ means don’t care.
The application software must avoid setting up a transmission (by clearing
or more TXE flags) and immediately request sleep mode (by setting
SLPRQ). It then depends on the exact sequence of operations whether
MSCAN08 starts transmitting or goes into sleep mode directly.
MSCAN08 Mode
MC68HC908GZ60 • MC68HC908GZ48 • MC68HC908GZ32 Data Sheet, Rev. 6
Power Down
Soft Reset
Normal
MSCAN08 SLEEPING
Sleep
or MSCAN08
Table 12-2. MSCAN08 versus CPU Operating Modes
MCU
SLPRQ = 1
Figure 12-7. Sleep Request/Acknowledge Cycle
SLPAK = 1
Figure
12-7). The time when the MSCAN08 enters sleep mode
MSCAN08 RUNNING
SLPAK = X
SFTRES = X
SLPRQ = 0
SLPAK = 0
MSCAN08
NOTE
STOP
.
(1)
CPU Mode
SLEEP REQUEST
SLPRQ = 1
SLPAK = 0
WAIT or RUN
SFTRES = 0
SFTRES = 1
SFTRES = 0
SLPAK = 1
SLPAK = 0
SLPAK = 0
MCU
Low-Power Modes
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