s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 258

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

I/O Ports
23.8.2 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.
DDRG[2:0] — Data Direction Register G Bits
Figure 23-22
258
These read/write bits control port G data direction. Reset clears DDRG[2:0], configuring all port G pins
as inputs.
1 = Corresponding port G pin configured as output
0 = Corresponding port G pin configured as input
shows the port G I/O logic.
Address:
Avoid glitches on port G pins by writing to the port G data register before
changing data direction register G bits from 0 to 1.
Reset:
Read:
Write:
READ DDRG ($000E)
WRITE DDRG ($000E)
WRITE PTG ($000A)
READ PTG ($000A)
$000E
Bit 7
R
R
0
0
Figure 23-21. Data Direction Register G (DDRG)
= Reserved
R
6
0
0
RESET
Figure 23-22. Port G I/O Circuit
MC68HC908AZ32A Data Sheet, Rev. 2
R
5
0
0
NOTE
DDRGx
PTGx
R
4
0
0
R
3
0
0
DDRG2
2
0
DDRG1
1
0
Freescale Semiconductor
DDRG0
Bit 0
PTGx
0