Input/Output (I/O) Ports
Port C
MC68HC908AB32
—
Rev. 1.0
Technical Data
MOTOROLA
Input/Output (I/O) Ports
321
PTC[5:0] — Port C Data Bits
These read/write bits are software programmable. Data direction of
each port C pin is under the control of the corresponding bit in data
direction register C. Reset has no effect on port C data.
MCLK — T12 System Clock
The system clock is driven out of the PTC2 pin when MCLKEN is set.
17.5.2 Data Direction Register C (DDRC)
Data direction register C determines whether each port C pin is an input
or an output. Writing a logic 1 to a DDRC bit enables the output buffer
for the corresponding port C pin; a logic 0 disables the output buffer.
MCLKEN — T12 System Clock Enable Bit
This read/write bit enables MCLK to be an output signal on PTC2 pin.
Reset clears MCLKEN.
1 = PTC2 pin configured as MCLK output
0 = PTC2 pin configured as standard I/O pin
DDRC[5:0] — Data Direction Register C Bits
These read/write bits control port C data direction. Reset clears
DDRC[5:0], configuring all port C pins as inputs.
1 = Corresponding port C pin configured as output
0 = Corresponding port C pin configured as input
NOTE:
Avoid glitches on port C pins by writing to the port C data register before
changing data direction register C bits from 0 to 1.
the port C I/O logic.
Address:
$0006
Bit 7
6
5
4
3
2
1
Bit 0
Read:
MCLKEN
0
DDRC5
DDRC4
DDRC3
DDRC2
DDRC1
DDRC0
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 17-9. Data Direction Register B (DDRB)
Summary of Contents for MC68HC908AB32
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Page 68: ...FLASH Memory Technical Data MC68HC908AB32 Rev 1 0 68 FLASH Memory MOTOROLA ...
Page 84: ...EEPROM Technical Data MC68HC908AB32 Rev 1 0 84 EEPROM MOTOROLA ...
Page 390: ...Ordering Information Technical Data MC68HC908AB32 Rev 1 0 390 Ordering Information MOTOROLA ...
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