mc68hc908lb8 Freescale Semiconductor, Inc, mc68hc908lb8 Datasheet - Page 139

• Manufacturer Part Number: mc68hc908lb8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

DDRC1–DDRC0 — Data Direction Register C Bits
Figure 14-11
When bit DDRCx is a 1, reading address $0002 reads the PTCx data latch. When bit DDRCx is a 0,
reading address $0002 reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit.
Freescale Semiconductor
These read/write bits control port C data direction. Reset clears DDRC1–DDRC0, configuring all port
C pins as inputs.
1 = Corresponding port C pin configured as output
0 = Corresponding port C pin configured as input
shows the port C I/O logic.
Address:
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.
Figure 14-11
Reset:
Read:
Write:
READ DDRC ($0006)
WRITE DDRC ($0006)
WRITE PTC ($0002)
READ PTC ($0002)
PTCPUEx
$0006
Bit 7
0
0
Figure 14-10. Data Direction Register C (DDRC)
does not apply to PTC2.
= Unimplemented
6
0
0
RESET
Figure 14-11. Port C I/O Circuit
MC68HC908LB8 Data Sheet, Rev. 1
V
DD
INTERNAL
PULLUP
DEVICE
5
0
0
Table 14-3
NOTE
NOTE
DDRCx
PTCx
4
0
0
summarizes the operation of the port C pins.
3
0
0
2
0
0
DDRC1
1
0
DDRC0
Bit 0
PTCx
0
Port C
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