Datasheet

Data Sheet ADuC7124/ADuC7126
Rev. C | Page 59 of 108
Table 79. GPxCON Registers
Name Address Default Value Access
GP0CON 0xFFFFF400 0x00000000 R/W
GP1CON 0xFFFFF404 0x00000000 R/W
GP2CON 0xFFFFF408 0x00000000 R/W
GP3CON 0xFFFFF40C 0x00000000 R/W
GP4CON 0xFFFFF410 0x00000000 R/W
GPxCON are the Port x control registers that select the function
of each pin of Port x, as described in Table 80.
Table 80. GPxCON MMR Bit Descriptions
Bit Description
[31:30] Reserved.
[29:28] Select function of Px.7 pin.
[27:26] Reserved.
[25:24] Select function of Px.6 pin.
[23:22] Reserved.
[21:20] Select function of Px.5 pin.
[19:18] Reserved.
[17:16] Select function of Px.4 pin.
[15:14] Reserved.
[13:12] Select function of Px.3 pin.
[11:10] Reserved.
[9:8] Select function of Px.2 pin.
[7:6] Reserved.
[5:4] Select function of Px.1 pin.
[3:2] Reserved.
[1:0] Select function of Px.0 pin.
Table 81. GPxPAR Registers
Name Address Default Value Access
GP0PAR 0xFFFFF42C 0x20000000 R/W
GP1PAR 0xFFFFF43C 0x00000000 R/W
GP2PAR 0xFFFFF44C 0x000000FF R/W
GP3PAR 0xFFFFF45C 0x00222222 R/W
GP4PAR 0xFFFFF46C 0x00000000 R/W
The GPxPAR registers program the parameters for Port 0, Port 1,
Port 2, Port 3, and Port 4. Note that the GPxDAT MMR must
always be written after changing the GPxPAR MMR.
Table 82. GPxPAR MMR Bit Descriptions
Bit Description
31 Reserved.
[30:29] Drive strength Px.7.
28 Pull-up disable Px.7.
27 Reserved.
[26:25] Drive strength Px.6.
24 Pull-up disable Px.6.
23 Reserved.
[22:21] Drive strength Px.5.
20 Pull-up disable Px.5.
19 Reserved.
[18:17] Drive strength Px.4.
Bit Description
16 Pull-up disable Px.4.
15 Reserved.
[14:13] Drive strength Px.3.
12 Pull-up disable Px.3.
11 Reserved.
[10:9] Drive strength Px.2.
8 Pull-up disable Px.2.
7 Reserved.
[6:5] Drive strength Px.1.
4 Pull-up disable Px.1.
3 Reserved.
[2:1] Drive strength Px.0.
0 Pull-up disable Px.0.
Table 83. GPIO Drive Strength Control Bits Descriptions
Control Bits Value Description
00 Medium drive strength.
01 Low drive strength.
1x High drive strength.
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
–24 –18 –12 –6 0 6 12 18 24
SINK/SOURCE CURRENT (mA)
SUPPLY VOLTAGE (V)
HIGH DRIVE STRENGTH
MEDIUM DRIVE STRENGTH
LOW DRIVE STRENGTH
09123-148
Figure 46. Programmable Strength for High Level
–0.4
–0.3
–0.2
–0.1
0.1
0
0.2
0.3
0.4
0.5
–24 –18 –12 –6 0 6 12 18 24
SINK/SOURCE CURRENT (mA)
SUPPLY VOLTAGE (V)
HIGH DRIVE STRENGTH
MEDIUM DRIVE STRENGTH
LOW DRIVE STRENGTH
09123-149
Figure 47. Programmable Strength for Low Level