MC68HC05JJ6 Datasheet, PDF (84/216 Pages) Freescale Semiconductor, Inc – General Release Specification Microcontrollers

Parallel Input/Output
7.4 Port B
Port B is an 8-bit, general-purpose bidirectional I/O port with the
following features:
• Programmable pulldown devices
• PB0 through PB4 shared with the analog subsystem
• PB3 and PB4 shared with the 16-bit programmable timer
• PB4 can be driven directly by the output of comparator 1
• PB5 through PB7 shared with the simple serial interface (SIOP)
• High current sinking capability to 15 mA on the PB4 pin
• High current sourcing capability to 5 mA on the PB4 pin
7.4.1 Port B Data Register
The port B data register 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.
$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
Alternate: SCK
SDI
SDO CMP1 TCAP
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.
General Release Specification
84
MC68HC05JJ6/MC68HC05JP6 — Rev. 3.2
Parallel Input/Output
Freescale Semiconductor