MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 109

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

MC68HC912DT128A — Rev 4.0
MOTOROLA
NDBE — No Data Bus Enable
CGMTE — Clock Generator Module Testing Enable
PIPOE — Pipe Status Signal Output Enable
NECLK — No External E Clock
In peripheral mode, the PEAR register is not accessible for reads or
writes. However, the CGMTE control bit is reset to one to configure
PE6 as a test output for the CGM module.
Normal: write once; Special: write anytime EXCEPT the first. Read
anytime.
The NDBE bit has no effect in Single Chip or Peripheral Modes and
PE7 is defaulted to the CAL function if CALE bit is set in PEAR
register or to an I/O otherwise.
Normal: write never; Special: write anytime EXCEPT the first time.
Read anytime.
Normal: write once; Special: write anytime EXCEPT the first time.
Read anytime.
Normal single chip: write once; special single chip: write anytime; all
other modes: write never.
Read anytime. In peripheral mode, E is an input and in all other
modes, E is an output.
0 = PE7 is used for DBE, external control of data enable on
1 = PE7 is CAL function if CALE bit is set in PEAR register or
0 = PE6 is general-purpose I/O or pipe output.
1 = PE6 is a test signal output from the CGM module (no effect in
0 = PE[6:5] are general-purpose I/O (if CGMTE = 1, PE6 is a test
1 = PE[6:5] are outputs and indicate the state of the instruction
memories, or inverted E clock.
general-purpose I/O otherwise.
single chip or normal expanded modes). PIPOE = 1 overrides
this function and forces PE6 to be a pipe status output signal.
output signal from the CGM module).
queue (only effective in expanded modes).
Bus Control and Input/Output
Bus Control and Input/Output
Technical Data
Registers
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