MC68HC908AB32 MOTOROLA [Motorola, Inc], MC68HC908AB32 Datasheet - Page 335

• Manufacturer Part Number: MC68HC908AB32
• Description: HCMOS Microcontroller Unit
• Manufacturer: MOTOROLA [Motorola, Inc]

17.10 Port H
17.10.1 Port H Data Register (PTH)
17.10.2 Data Direction Register H (DDRH)
MC68HC908AB32
MOTOROLA
Alternative Function:
—
Rev. 1.0
Address:
Port H is a 2-bit special-function port that shares all two of its pins with
the keyboard interrupt (KBI) module.
The port H data register (PTH) contains a data latch for each of the two
port H pins.
PTH[1:0] — Port H Data Bits
KBD[4:3] — The keyboard interrupt enable bits, KBIE[4:3], in the
keyboard interrupt enable register (KBIER), enable the port H pins as
external interrupt pins. See
(KBI).
Data direction register H determines whether each port H pin is an input
or an output. Writing logic 1 to a DDRH bit enables the output buffer for
the corresponding port H pin; a logic 0 disables the output buffer.
Reset:
Read:
Write:
These read/write bits are software programmable. Data direction of
each port H pin is under the control of the corresponding bit in data
direction register H. Reset has no effect on port H data.
Freescale Semiconductor, Inc.
For More Information On This Product,
$000B
Bit 7
Figure 17-25. Port H Data Register (PTH)
0
Go to: www.freescale.com
Input/Output (I/O) Ports
6
0
5
0
Section 19. Keyboard Interrupt Module
Unaffected by reset
4
0
3
0
2
0
Input/Output (I/O) Ports
PTH1
KBD4
1
Technical Data
PTH0
KBD3
Bit 0
Port H
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