mc68hc916y3 Freescale Semiconductor, Inc, mc68hc916y3 Datasheet - Page 389

• Manufacturer Part Number: mc68hc916y3
• Description: Mc68hc16y3 16 Bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

D.2.10 Port E Data Direction Register
DDRAB — Port A/B Data Direction Register
DDRE — Port E Data Direction Register
D.2.11 Port E Pin Assignment Register
PEPAR — Port E Pin Assignment
MC68HC16Y3/916Y3
USER’S MANUAL
15
15
0
RESET:
RESET:
The port E data direction register controls the direction of the port E pin drivers when
pins are configured for I/O. Setting a bit configures the corresponding pin as an output;
clearing a bit configures the corresponding pin as an input. This register can be read
or written at any time.
The port A/B data direction register controls the direction of the pin drivers for ports A
and B, respectively, when the pins are configured for I/O. Setting DDA or DDB to one
configures all pins in the corresponding port as outputs. Clearing DDA or DDB to zero
configures all pins in the corresponding port as inputs. Bits [15:10] are unimplemented
and will always read zero.
This register determines the function of port E pins. Setting a bit assigns the corre-
sponding pin to a bus control signal; clearing a bit assigns the pin to I/O port E. PE3 is
not connected to a pin. PEPA3 can be read and written, but has no function. Bits [15:8]
are unimplemented and will always read zero. Table D-4 displays port E pin
assignments.
14
0
13
0
NOTES:
1. The CPU16 does not support the RMC function for this pin. This bit is not
12
connected to a pin for I/O usage.
NOT USED
0
PEPAR Bit
PEPA7
PEPA6
PEPA5
PEPA4
PEPA3
PEPA2
PEPA1
PEPA0
Freescale Semiconductor, Inc.
11
0
For More Information On This Product,
Table D-4 Port E Pin Assignments
10
0
Go to: www.freescale.com
REGISTER SUMMARY
DDA
9
Port E Signal
DDB
8
8
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
PEPA7 PEPA6 PEPA5 PEPA4 PEPA3 PEPA2 PEPA1 PEPA0
DATA8 DATA8 DATA8 DATA8 DATA8 DATA8 DATA8 DATA8
DDE7
7
0
7
DDE6
6
0
6
DDE5
Bus Control Signal
5
0
5
DSACK1
DSACK0
DDE4
AVEC
SIZ1
SIZ0
4
0
4
—
AS
DS
1
DDE3
3
0
3
DDE2
2
0
2
$YFFA14
$YFFA15
$YFFA17
MOTOROLA
DDE1
1
0
1
DDE0
D-11
0
0
0