LM3S316 Datasheet, PDF (136/421 Pages) List of Unclassifed Manufacturers – Microcontroller

General-Purpose Input/Outputs (GPIOs)
Register 12: GPIO 4-mA Drive Select (GPIODR4R), offset 0x504
The GPIODR4R register is the 4-mA drive control register. It allows for each GPIO signal in the
port to be individually configured without affecting the other pads. When writing the DRV4 bit for a
GPIO signal, the corresponding DRV2 bit in the GPIODR2R register and the DRV8 bit in the
GPIODR8R register are automatically cleared by hardware.
GPIO 4-mA Drive Select (GPIODR4R)
Offset 0x504
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
reserved
Type
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
reserved
DRV4
Type
RO
RO
RO
RO
RO
RO
RO
RO
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
31:8
7:0
Name
reserved
DRV4
Type
RO
R/W
Reset
0
0x00
Description
Reserved bits return an indeterminate value, and should never
be changed.
Output Pad 4-mA Drive Enable
A write of 1 to either GPIODR2[n] or GPIODR8[n] clears the
corresponding 4-mA enable bit. The change is effective on the
second clock cycle after the write.
136
April 27, 2007
Preliminary