Port B; Port B Data Register (Ptb) - Freescale Semiconductor MC68HC08KH12 Datasheet

12.4 Port B

12.4.1 Port B Data Register (PTB)

Advance Information
188
Table 12-2. Port A Pin Functions
DDRA
PTA Bit
Bit
(1)
0 X
1 X
1. X = don't care
2. Hi-Z = high impedance
3. Writing affects data register, but does not affect input.
Port B is an 8-bit general-purpose bidirectional I/O port with software
configurable pullups.
The port B data register contains a data latch for each of the eight port B
pins.
Address: $0001
Bit 7 6
Read:
PTB7 PTB6
Write:
Reset:
Figure 12-4. Port B Data Register (PTB)
PTB[7:0] — Port B Data Bits
These read/write bits are software-programmable. Data direction of
each port B pin is under the control of the corresponding bit in data
direction register B. Reset has no effect on port B data.
The port B pullup enable bit, PBP, in the port option control register
(POC) enables pullups on port B pins if the respective pin is configured
as an input. (See 12.9 Port
Accesses
I/O Pin to DDRA
Mode
Read/Write
(2)
Input, Hi-Z DDRA[7:0]
Output DDRA[7:0]
5 4 3
PTB5 PTB4 PTB3
Unaffected by reset
Options.).
Accesses to PTA
Read Write
Pin PTA[7:0]
PTA[7:0] PTA[7:0]
2 1 Bit 0
PTB2 PTB1 PTB0
MC68HC(7)08KH12 Rev. 1.1
—
Freescale Semiconductor
(3)