Datasheet

MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Freescale Semiconductor 249
Chapter 22
Input/Output Ports
22.1 Introduction
On the MC68HC908AZ60A and 64-pin MC68HC908AS60A, fifty bidirectional input/output (I/O) form
seven parallel ports. On the52-pin MC68HC908AS60A, forty bidirectional input/output (I/O) form six
parallel ports. All I/O pins are programmable as inputs or outputs.
NOTE
Connect any unused I/O pins to an appropriate logic level, either V
DD
or
V
SS
. Although the I/O ports do not require termination for proper operation,
termination reduces excess current consumption and the possibility of
electrostatic damage.
Addr. Register Name Bit 7654321Bit 0
$0000 Port A Data Register (PTA) PTA7 PTA6 PTA5 PTA4 PTA3 PTA2 PTA1 PTA0
$0001 Port B Data Register (PTB) PTB7 PTB6 PTB5 PTB4 PTB3 PTB2 PTB1 PTB0
$0002 Port C Data Register (PTC) 0 0 PTC5 PTC4 PTC3 PTC2 PTC1 PTC0
$0003 Port D Data Register (PTD) PTD7 PTD6 PTD5 PTD4 PTD3 PTD2 PTD1 PTD0
$0004 Data Direction Register A (DDRA) DDRA7 DDRA6 DDRA5 DDRA4 DDRA3 DDRA2 DDRA1 DDRA0
$0005 Data Direction Register B (DDRB) DDRB7 DDRB6 DDRB5 DDRB4 DDRB3 DDRB2 DDRB1 DDRB0
$0006 Data Direction Register C (DDRC) MCLKEN 0 DDRC5 DDRC4 DDRC3 DDRC2 DDRC1 DDRC0
$0007 Data Direction Register D (DDRD) DDRD7 DDRD6 DDRD5 DDRD4 DDRD3 DDRD2 DDRD1 DDRD0
$0008 Port E Data Register (PTE) PTE7 PTE6 PTE5 PTE4 PTE3 PTE2 PTE1 PTE0
$0009 Port F Data Register (PTF) 0 PTF6 PTF5 PTF4 PTF3 PTF2 PTF1 PTF0
$000A Port G Data Register (PTG) 00000PTG2PTG1PTG0
$000B Port H Data Register (PTH) 000000PTH1PTH0
$000C Data Direction Register E (DDRE) DDRE7 DDRE6 DDRE5 DDRE4 DDRE3 DDRE2 DDRE1 DDRE0
$000D Data Direction Register F (DDRF) 0 DDRF6 DDRF5 DDRF4 DDRF3 DDRF2 DDRF1 DDRF0
$000E Data Direction Register G (DDRG) 00000DDRG2DDRG1DDRG0
$000FData Direction Register H (DDRH)000000DDRH1DDRH0
Figure 22-1. I/O Port Register Summary