MC908AZ60ACFUER Datasheet, PDF (263/414 Pages) Freescale Semiconductor, Inc – To provide the most up-to-date information, the revision of our documents on the World Wide Web will be the most current. Your printed copy may be an earlier revision. To verify you have the latest information available, refer to:

Port G
22.8 Port G
Port G is a 3-bit special function port that shares all of its pins with the keyboard interrupt module (KBD).
Note that Port G is only available on 64-pin package options.
22.8.1 Port G Data Register
The port G data register contains a data latch for each of the three port G pins.
Address:
Read:
Write:
Reset:
Alternative
Function:
$000A
Bit 7
0
R
R
6
5
4
3
2
0
0
0
0
PTG2
R
R
R
R
Unaffected by Reset
KBD2
= Reserved
Figure 22-20. Port G Data Register (PTG)
1
PTG1
KBD1
Bit 0
PTG0
KBD0
PTG[2:0] — Port G Data Bits
These read/write bits are software programmable. Data direction of each port G pin is under the control
of the corresponding bit in data direction register G. Reset has no effect on PTG[2:0].
KBD[2:0] — Keyboard Wakeup pins
The keyboard interrupt enable bits, KBIE[2:0], in the keyboard interrupt control register, enable the port
G pins as external interrupt pins (See Chapter 24 Keyboard Module (KBI)). Enabling an external
interrupt pin will override the corresponding DDRGx.
22.8.2 Data Direction Register G
Data direction register G determines whether each port G pin is an input or an output. Writing a logic 1 to
a DDRG bit enables the output buffer for the corresponding port G pin; a logic 0 disables the output buffer.
Address:
Read:
Write:
Reset:
$000E
Bit 7
6
5
4
3
2
1
0
0
0
0
0
DDRG2 DDRG1
R
R
R
R
R
0
0
0
0
0
0
0
R
= Reserved
Figure 22-21. Data Direction Register G (DDRG)
Bit 0
DDRG0
0
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Freescale Semiconductor
263