mc68hc908mr8 Freescale Semiconductor, Inc, mc68hc908mr8 Datasheet - Page 283

• Manufacturer Part Number: mc68hc908mr8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

MC68HC908MR8 — Rev 4.1
Freescale Semiconductor
When bit DDRAx is a logic 1, reading address $0000 reads the PTAx
data latch. When bit DDRAx is a logic 0, reading address $0000 reads
the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit.
the operation of the port A pins.
1. X = don’t care
2. Hi-Z = high impedance
3. Writing affects data register, but does not affect input.
DDRA
Bit
0
1
READ DDRA ($0004)
WRITE DDRA ($0004)
WRITE PTA ($0000)
READ PTA ($0000)
Input/Output (I/O) Ports
PTA
X
Bit
X
(1)
Table 14-1. Port A Pin Functions
Figure 14-4. Port A I/O Circuit
RESET
Input, Hi-Z
I/O Pin
Output
Mode
(2)
DDRAx
PTAx
Read/Write
DDRA[6:0]
DDRA[6:0]
Accesses
to DDRA
Table 14-1
PTA[6:0]
Read
Accesses to PTA
Input/Output (I/O) Ports
Pin
summarizes
Technical Data
PTA[6:0]
PTA[6:0]
Write
Port A
PTAx
(3)
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