s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 259

• Manufacturer Part Number: s908az32ag2cfue
• Description: M68hc08 Microcontrollers 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

When bit DDRGx is a logic 1, reading address $000A reads the PTGx data latch. When bit DDRGx is a
logic 0, reading address $000A reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit.
23.9 Port H
Port H is a 2-bit special function port that shares all of its pins with the keyboard interrupt module (KBD).
Note that Port H is only available on 64-pin package options.
23.9.1 Port H Data Register
The port H data register contains a data latch for each of the two port H pins.
PTH[1:0] — Port H Data Bits
KBD[4:3] — Keyboard Wake-up pins
Freescale Semiconductor
These read/write bits are software programmable. Data direction of each port H pin is under the control
of the corresponding bit in data direction register H. Reset has no effect on PTH[1:0].
The keyboard interrupt enable bits, KBIE[4:3], in the keyboard interrupt control register, enable the port
H pins as external interrupt pins (See
Function:
X = don’t care
Hi-Z = high impedance
1. Writing affects data register, but does not affect input.
Address:
Alternate
Reset:
Read:
DDRG
Write:
Bit
0
1
$000B
Bit 7
R
R
0
PTG
Bit
Figure 23-23. Port H Data Register (PTH)
X
X
= Reserved
R
6
0
Table 23-7. Port G Pin Functions
MC68HC908AZ32A Data Sheet, Rev. 2
Input, Hi-Z
Chapter 22 Keyboard Module
I/O Pin
Output
Mode
R
5
0
Table 23-7
Unaffected by Reset
R
4
0
Accesses to
Read/Write
DDRG[2:0]
DDRG[2:0]
DDRG
summarizes the operation of the port G pins.
R
3
0
PTG[2:0]
Read
R
Pin
2
0
Accesses to PTG
(KBD)).
PTH1
KBD4
1
PTG[2:0]
PTG[2:0]
Write
PTH0
KBD3
Bit 0
(1)
Port H
259