MC68HC705JP7 Datasheet, PDF (90/242 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Freescale Semiconductor, Inc.
Parallel Input/Output
7.4 Port B
Port B is an 8-bit, general-purpose, bidirectional I/O port with these
features:
• Programmable pulldown devices
• PB0–PB4 are shared with the analog subsystem.
• PB3 and PB4 are shared with the 16-bit programmable timer.
• PB4 can be driven directly by the output of comparator 1.
• PB5–PB7 are shared with the simple serial interface (SIOP).
• High current sinking capability on the PB4 pin
• High current sourcing capability on the PB4 pin
7.4.1 Port B Data Register
The port B data register (PORTB) contains a bit for each of the port B
pins. When a port B pin is programmed to be an output, the state of its
data register bit determines the state of the output pin. When a port B pin
is programmed to be an input, reading the port B data register returns
the logic state of the pin. Reset has no effect on port B data.
Address: $0001
Bit 7
6
5
4
3
2
1
Bit 0
Read:
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
Write:
Reset:
Unaffected by reset
Alternate: SCK
SDI
SDO
AN4
AN3
AN2
AN1
AN0
Alternate: SCK
SDI
SDO TCMP TCAP AN2
AN1
AN0
Alternate: SCK
SDI
SDO CMP1 TCAP AN2
AN1
AN0
Figure 7-5. Port B Data Register (PORTB)
PB0-PB7 — Port B Data Bits
These read/write bits are software programmable. Data direction of
each bit is under the control of the corresponding bit in data direction
register B. Reset has no effect on port B data.
Advance Information
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MC68HC705JJ7 • MC68HC705JP7 — REV 4
Parallel Input/Output
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