MC68HC908GT16_07 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GT16_07 Datasheet - Page 192

• Manufacturer Part Number: MC68HC908GT16_07
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

System Integration Module (SIM)
15.6.2 Stop Mode
In stop mode, the SIM counter is reset and the system clocks are disabled. An interrupt request from a
module can cause an exit from stop mode. Stacking for interrupts begins after the selected stop recovery
time has elapsed. Reset or break also causes an exit from stop mode.
The SIM disables the clock generator module outputs (CGMOUT and CGMXCLK) in stop mode, stopping
the CPU and peripherals. Stop recovery time is selectable using the SSREC bit in CONFIG1. If SSREC
is set, stop recovery is reduced from the normal delay of 4096 CGMXCLK cycles down to 32. This is ideal
for applications using canned oscillators that do not require long startup times from stop mode.
The SIM counter is held in reset from the execution of the STOP instruction until the beginning of stop
recovery. It is then used to time the recovery period.
192
EXITSTOPWAIT
Note: EXITSTOPWAIT = RST pin, CPU interrupt or break interrupt interrupt
All applications should use the full stop recovery time by clearing the
SSREC bit unless OSCENINSTOP is set in CONFIG2.
To minimize stop current, all pins configured as inputs should be driven to
a 1 or 0.
CGMXCLK
RST
MC68HC908GT16 • MC68HC908GT8 • MC68HC08GT16 Data Sheet, Rev. 5.0
IDB
IAB
IDB
IAB
Figure 15-16. Wait Recovery from Interrupt or Break
$A6
Figure 15-17. Wait Recovery from Internal Reset
$A6
$6E0B
$A6
$6E0B
$A6
$A6
$A6
CYCLES
$6E0C
32
NOTE
NOTE
$01
Figure 15-18
$00FF
CYCLES
32
$0B
$00FE
$6E
shows stop mode entry timing.
RST VCT H
$00FD
RST VCT L
$00FC
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