Input/Output (I/O) Ports
Technical Data
MC68HC908AB32
—
Rev. 1.0
336
Input/Output (I/O) Ports
MOTOROLA
DDRH[1:0] — Data Direction Register H Bits
These read/write bits control port H data direction. Reset clears
DDRH[1:0], configuring all port H pins as inputs.
1 = Corresponding port H pin configured as output
0 = Corresponding port H pin configured as input
NOTE:
Avoid glitches on port H pins by writing to the port H data register before
changing data direction register H bits from 0 to 1.
the port H I/O logic.
Figure 17-27. Port H I/O Circuit
When DDRHx is a logic 1, reading address $000B reads the PTHx data
latch. When DDRHx is a logic 0, reading address $000B reads the
voltage level on the pin. The data latch can always be written, regardless
of the state of its data direction bit.
summarizes the operation of the port H pins.
Address:
$000F
Bit 7
6
5
4
3
2
1
Bit 0
Read:
0
0
0
0
0
0
DDRH1
DDRH0
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 17-26. Data Direction Register H (DDRH)
READ DDRH ($000F)
WRITE DDRH ($000F)
RESET
WRITE PTH ($000B)
READ PTH ($000B)
PTHx
DDRHx
PTHx
INTERNAL D
AT
A
B
U
S
KBI
Содержание MC68HC908AB32
Страница 1: ...MC68HC908AB32 D REV 1 0 MC68HC908AB32 HCMOS Microcontroller Unit TECHNICAL DATA ...
Страница 2: ......
Страница 68: ...FLASH Memory Technical Data MC68HC908AB32 Rev 1 0 68 FLASH Memory MOTOROLA ...
Страница 84: ...EEPROM Technical Data MC68HC908AB32 Rev 1 0 84 EEPROM MOTOROLA ...
Страница 108: ...Central Processor Unit CPU Technical Data MC68HC908AB32 Rev 1 0 108 Central Processor Unit CPU MOTOROLA ...
Страница 130: ...System Integration Module SIM Technical Data MC68HC908AB32 Rev 1 0 130 System Integration Module SIM MOTOROLA ...
Страница 338: ...Input Output I O Ports Technical Data MC68HC908AB32 Rev 1 0 338 Input Output I O Ports MOTOROLA ...
Страница 364: ...Low Voltage Inhibit LVI Technical Data MC68HC908AB32 Rev 1 0 364 Low Voltage Inhibit LVI MOTOROLA ...
Страница 386: ...Electrical Specifications Technical Data MC68HC908AB32 Rev 1 0 386 Electrical Specifications MOTOROLA ...
Страница 390: ...Ordering Information Technical Data MC68HC908AB32 Rev 1 0 390 Ordering Information MOTOROLA ...
Страница 391: ......