Datasheet
Input/Output (I/O) Ports
Data Sheet MC68HC908LJ24/LK24 — Rev. 2.1
390 Input/Output (I/O) Ports Freescale Semiconductor
18.6 Port D
Port D is an 8-bit special function port that shares its pins with the serial
peripheral interface (SPI) module, keyboard interrupt module, RTC
module, MMIIC module, and timer modules.
18.6.1 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.
KBI[7:4] — Keyboard Interrupt Channels 7 to 4
KBI[7:4] are pins used for the keyboard interrupt input. The
corresponding input, KBI[7:4], can be enabled in the keyboard
interrupt enable register, KBIER. Port pins used as KBI input will
override any control from the port I/O logic. See Section 20.
Keyboard Interrupt Module (KBI).
Address: $0003
Bit 7654321Bit 0
Read:
PTD7 PTD6 PTD5 PTD4 PTD3 PTD2 PTD1 PTD0
Write:
Reset: Unaffected by reset
Alternative Function:
KBI7/
SDA*
KBI6/
SCL*
KBI5/
T2CLK*
KBI4/
T1CLK*
SPSCK/
CALOUT*
MOSI MISO
SS
/
CALIN*
* These port pins are shared with two other modules. For each of the pins, ONLY enable ONE module at any one
time to avoid pin contention.
Figure 18-13. Port D Data Register (PTD)
