mc68hc912dg128 Freescale Semiconductor, Inc, mc68hc912dg128 Datasheet - Page 100

• Manufacturer Part Number: mc68hc912dg128
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Bus Control and Input/Output
DDRE — Port E Data Direction Register
PEAR — Port E Assignment Register
Technical Data
100
RESET:
RESET:
RESET:
RESET:
RESET:
RESET:
DDE7
Bit 7
NDBE
BIT 7
0
0
0
1
1
0
CGMTE
DDE6
6
0
6
0
0
1
0
0
This register determines the primary direction for each port E pin
configured as general-purpose I/O.
PE[1:0] are associated with XIRQ and IRQ and cannot be configured as
outputs. These pins can be read regardless of whether the alternate
interrupt functions are enabled.
This register is not in the map in peripheral mode and expanded modes
while the EME control bit is set.
Read and write anytime.
The PEAR register is used to choose between the general-purpose I/O
functions and the alternate bus control functions of Port E. When an
Freescale Semiconductor, Inc.
For More Information On This Product,
0 = Associated pin is a high-impedance input
1 = Associated pin is an output
DDE5
PIPOE
5
0
5
0
1
0
0
1
Bus Control and Input/Output
Go to: www.freescale.com
NECLK
DDE4
4
0
4
0
0
1
1
0
LSTRE
DDE3
3
0
3
0
1
0
0
1
DDE2
RDWE
2
0
2
0
1
0
0
1
MC68HC912DG128 — Rev 3.0
CALE
1
0
0
1
0
0
0
0
0
DBENE
BIT 0
Bit 0
0
0
0
0
0
0
0
MOTOROLA
single chip
single chip
Expanded
Expanded
Peripheral
Normal
Special
Normal
Special
$000A
$0009