MC68HC908AB32 MOTOROLA [Motorola, Inc], MC68HC908AB32 Datasheet - Page 328

• Manufacturer Part Number: MC68HC908AB32
• Description: HCMOS Microcontroller Unit
• Manufacturer: MOTOROLA [Motorola, Inc]

Input/Output (I/O) Ports
17.7.2 Data Direction Register E (DDRE)
Technical Data
328
NOTE:
Address:
Data direction register E determines whether each port E pin is an input
or an output. Writing a logic 1 to a DDRE bit enables the output buffer for
the corresponding port E pin; a logic 0 disables the output buffer.
DDRE[7:0] — Data Direction Register E Bits
Avoid glitches on port E pins by writing to the port E data register before
changing data direction register E bits from 0 to 1.
the port E I/O logic.
Reset:
Read:
Write:
These read/write bits control port E data direction. Reset clears
DDRE[7:0], configuring all port E pins as inputs.
Freescale Semiconductor, Inc.
For More Information On This Product,
1 = Corresponding port E pin configured as output
0 = Corresponding port E pin configured as input
DDRE7
READ DDRE ($000C)
WRITE DDRE ($000C)
WRITE PTE ($0008)
READ PTE ($0008)
$000C
Bit 7
Figure 17-16. Data Direction Register E (DDRE)
0
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Input/Output (I/O) Ports
DDRE6
6
0
Figure 17-17. Port E I/O Circuit
RESET
DDRE5
5
0
DDRE4
DDREx
PTEx
4
0
DDRE3
3
0
MC68HC908AB32
DDRE2
Figure 17-17
2
0
DDRE1
1
0
MOTOROLA
—
shows
Rev. 1.0
DDRE0
Bit 0
0
PTEx