MC68HC908AS60ACFN FREESCALE [Freescale Semiconductor, Inc], MC68HC908AS60ACFN Datasheet - Page 251

• Manufacturer Part Number: MC68HC908AS60ACFN
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

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.
Freescale Semiconductor
X = don’t care
Hi-Z = high impedance
1. Writing affects data register, but does not affect input.
DDRA
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Bit
0
1
READ DDRA ($0004)
WRITE DDRA ($0004)
WRITE PTA ($0000)
READ PTA ($0000)
PTA
Bit
X
X
Table 22-1. Port A Pin Functions
RESET
Figure 22-4. Port A I/O Circuit
I/O Pin Mode
Input, Hi-Z
Output
Table 22-1
DDRAx
PTAx
Accesses to
Read/Write
DDRA[7:0]
DDRA[7:0]
DDRA
summarizes the operation of the port A pins.
PTA[7:0]
Read
Pin
Accesses to PTA
PTA[7:0]
PTA[7:0]
Write
PTAx
(1)
Port A
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