mc68hc908jl16 Freescale Semiconductor, Inc, mc68hc908jl16 Datasheet - Page 48

• Manufacturer Part Number: mc68hc908jl16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

System Integration Module (SIM)
4.2.3 Clocks in Stop Mode and Wait Mode
Upon exit from stop mode by an interrupt, break, or reset, the SIM allows ICLK to clock the SIM counter.
The CPU and peripheral clocks do not become active until after the stop delay time-out. This time-out is
selectable as 4096 or 32 ICLK cycles. (See
In wait mode, the CPU clocks are inactive. The SIM also produces two sets of clocks for other modules.
Refer to the wait mode subsection of each module to see if the module is active or inactive in wait mode.
Some modules can be programmed to be active in wait mode.
4.3 Reset and System Initialization
The MCU has these reset sources:
All of these resets produce the vector $FFFE–$FFFF ($FEFE–$FEFF in Monitor mode) and assert the
internal reset signal (IRST). IRST causes all registers to be returned to their default values and all
modules to be returned to their reset states.
An internal reset clears the SIM counter (see
the resets sets a corresponding bit in the reset status register (RSR). (See
4.3.1 External Pin Reset
The RST pin circuits include an internal pull-up device. Pulling the asynchronous RST pin low halts all
processing. The PIN bit of the reset status register (RSR) is set as long as RST is held low for a minimum
of 67 ICLK cycles, assuming that the POR was not the source of the reset. See
Figure 4-4
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Power-on reset module (POR)
External reset pin (RST)
Computer operating properly module (COP)
Low-voltage inhibit module (LVI)
Illegal opcode
Illegal address
ICLK
shows the relative timing.
RST
IAB
PC
Reset Type
All others
POR
Figure 4-4. External Reset Timing
MC68HC908JL16 Data Sheet, Rev. 1.1
Table 4-2. PIN Bit Set Timing
4.6.2 Stop
4.4 SIM
Number of Cycles Required to Set PIN
Counter), but an external reset does not. Each of
4163 (4096 + 64 + 3)
Mode.)
67 (64 + 3)
VECT H
VECT L
4.7 SIM
Table 4-2
Freescale Semiconductor
Registers.)
for details.