Data Sheet — MC68HC908MR32 • MC68HC908MR16
Section 10. Input/Output (I/O) Ports (PORTS)
10.1 Introduction
Thirty-seven bidirectional input-output (I/O) pins and seven input pins form six
parallel ports. All I/O pins are programmable as inputs or outputs.
When using the 56-pin package version:
•
•
•
Set the data direction register bits in DDRC such that bit 1 is written to a
logic 1 (along with any other output bits on port C).
Set the data direction register bits in DDRE such that bits 0, 1, and 2 are
written to a logic 1 (along with any other output bits on port E).
Set the data direction register bits in DDRF such that bits 0, 1, 2, and 3 are
written to a logic 1 (along with any other output bits on port F).
NOTE:
Connect any unused I/O pins to an appropriate logic level, either VDD or VSS
Although PWM6–PWM1 do not require termination for proper operation,
.
termination reduces excess current consumption and the possibility of electrostatic
damage.
Addr.
Register Name
Bit 7
6
5
4
3
2
1
Bit 0
Read:
Write:
Reset:
Read:
Write:
Reset:
Read:
Write:
Reset:
Read:
Write:
Reset:
Port A Data Register
(PTA)
See page 113.
PTA7
PTA6
PTA5
PTA4
PTA3
PTA2
PTA1
PTA0
$0000
Unaffected by reset
PTB4 PTB3
Unaffected by reset
PTC4 PTC3
Unaffected by reset
Port B Data Register
(PTB)
See page 115.
PTB7
PTB6
PTC6
PTB5
PTC5
PTB2
PTC2
PTB1
PTC1
PTB0
PTC0
$0001
$0002
$0003
0
Port C Data Register
(PTC)
See page 117.
R
0
PTD6
R
PTD5
R
PTD4
R
PTD3
R
PTD2
R
PTD1
R
PTD0
R
Port D Data Register
(PTD)
See page 119.
R
Unaffected by reset
R
= Reserved
Figure 10-1. I/O Port Register Summary
MC68HC908MR32 • MC68HC908MR16 — Rev. 6.0
MOTOROLA Input/Output (I/O) Ports (PORTS)
Data Sheet
111
FREESCALE [ Freescale ]
