XC908AS60ACFU Motorola Semiconductor Products, XC908AS60ACFU Datasheet - Page 152

• Manufacturer Part Number: XC908AS60ACFU
• Description: MC68HC908AZ60A, MC68HC908AS60A Hcmos Microcontroller Unit Technical Data
• Manufacturer: Motorola Semiconductor Products

System Integration Module (SIM)
9.4 Reset and System Initialization
9.4.1 External Pin Reset
Technical Data
152
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
156), but an external reset does not. Each of the resets sets a
corresponding bit in the SIM reset status register (SRSR) (see
Registers
Pulling the asynchronous RST pin low halts all processing. The PIN bit
of the SIM reset status register (SRSR) is set as long as RST is held low
for a minimum of 67 CGMXCLK cycles, assuming that neither the POR
nor the LVI was the source of the reset. See
9-4
•
•
•
•
•
•
shows the relative timing.
Power-on reset module (POR)
External reset pin (RST)
Computer operating properly module (COP)
Low-voltage inhibit module (LVI)
Illegal opcode
Illegal address
System Integration Module (SIM)
Reset Type
on page 165).
All others
POR/LVI
Table 9-3. PIN Bit Set Timing
Number of Cycles Required to Set PIN
4163 (4096 + 64 + 3)
67 (64 + 3)
Table 9-3
MC68HC908AZ60A — Rev 2.0
SIM Counter
for details.
on page
MOTOROLA
SIM
Figure