Datasheet

Input/Output (I/O) Ports
MC68HC908AB32 — Rev. 1.1 Technical Data
Freescale Semiconductor Input/Output (I/O) Ports
323
17.6 Port D
Port D is an 8-bit special function port that shares two of its pins with the
timer interface module (see Section 11. Timer Interface Module A
(TIMA) and Section 12. Timer Interface Module B (TIMB)). Each
port D pin has 15mA current drive (sink) and programmable pullup.
17.6.1 Port D Data Register (PTD)
The port D data register contains a data latch for each of the eight port D
pins.
PTD[7:0] — Port D Data Bits
These read/write bits are software programmable. Data direction of
each port D pin is under the control of the corresponding bit in data
direction register D. Reset has no effect on port D data.
TACLK — Timer A Clock Input
The PTD6 pin becomes TACLK, the timer A (TIMA) external clock
input when the TIMA prescaler select bits, PS[2:0] = 111. See
Section 11. Timer Interface Module A (TIMA).
TBCLK — Timer B Clock Input
The PTD4 pin becomes TBCLK, the timer B (TIMB) external clock
input when the TIMB prescaler select bits, PS[2:0] = 111. See
Section 12. Timer Interface Module B (TIMB).
Address: $0003
Bit 7654321Bit 0
Read:
PTD7 PTD6 PTD5 PTD4 PTD3 PTD2 PTD1 PTD0
Write:
Reset: Unaffected by reset
Alternative Function:
TACLK TBCLK
Additional Functions:
15mA sink 15mA sink 15mA sink 15mA sink 15mA sink 15mA sink 15mA sink 15mA sink
Input pullup Input pullup Input pullup Input pullup Input pullup Input pullup Input pullup Input pullup
Figure 17-11. Port D Data Register (PTD)