M68HC11ERG Datasheet, PDF (40/60 Pages) Motorola, Inc – M68HC11E Series Programming Reference Guide

M68HC11ERG/AD
Parallel I/O Control (PIOC)
Address: $1002
Bit 7
6
5
4
3
2
1
Bit 0
Read:
STAF
STAI
CWOM HNDS
OIN
PLS
EGA
INVB
Write:
Reset: 0
0
0
0
0
U
1
1
U = Unaffected
STAF — Strobe A Interrupt Status Flag
STAF is set when the selected edge occurs on strobe A. This bit can be
cleared by a read of PIOC with STAF set followed by a read of PORTCL
(simple strobed or full input handshake mode) or a write to PORTCL (output
handshake mode).
0 = No active edge detected
1 = Selected active edge detected
STAI — Strobe A Interrupt Enable Mask
0 = STAF does not request interrupt
1 = STAF requests interrupt
CWOM — Port C Wired-OR Mode (affects all eight port C pins)
0 = Port C outputs are normal CMOS outputs.
1 = Port C outputs are open-drain outputs.
HNDS — Handshake Mode Bit
0 = Simple strobe mode
1 = Full input or output handshake mode
OIN — Output or Input Handshake Select
HNDS must be set to 1 for this bit to have meaning.
0 = Input handshake
1 = Output handshake
PLS — Pulsed/Interlocked Handshake Operation
HNDS must be set to 1 for this bit to have meaning. When interlocked
handshake is selected, strobe B is active until the selected edge of strobe A
is detected.
0 = Interlocked handshake
1 = Pulsed handshake (Strobe B pulses high for two E-clock cycles.)
EGA — Active Edge for Strobe A
0 = STRA falling edge selected
1 = STRA rising edge selected
INVB — Invert Strobe B
0 = Active level is logic 0.
1 = Active level is logic 1.
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M68HC11E Series Programming Reference Guide
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