NXP Semiconductors freescale semiconductor MC13211, Reference Manual

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Modem SPI Register Descriptions
MC1321x Reference Manual, Rev. 1.6
5-16 Freescale Semiconductor
5.14 GPIO_Dir - Register 0B
The GPIO_Dir Register 0B contains control bits for GPIO1 through GPIO7 that configure the data
direction of each GPIO as well as a control field that sets the output drive strength of GPIO1 through
GPIO4. Each GPIO bit has a corresponding bit to set the GPIO as an output and a separate corresponding
bit to set the GPIO as an input. If both enable bits are set simultaneously for a given GPIO, the GPIO is
configured as an input (input setting wins). During a hardware reset on RST, all the GPIO are tristated and
the GPIO default to inputs.
Register 0B
0x0B
BIT 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
gpi
o12
34_d
rv[1:0]
gpio
7_o
en
gpio
6_o
en
gpio
5_o
en
gpio
4_o
en
gpio
3_o
en
gpio
2_o
en
gpio
1_o
en
gpio
7_i
en
gpio
6_i
en
gpio
5_i
en
gpio
4_i
en
gpio
3_i
en
gpio
2_i
en
gpio
1_i
en
TYPE r/w r/w r/w r/w r/w r/w r/w 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 1 1 1 1 1 1 1
0x007F
Table 5-14. Register 0B Description
Name Description Operation
Bits 15-14 gpio1234_drv[1:0] — These bits select output drive strength for
GPIO1 through GPIO4.
00 (default) = lowest drive strength;
11 = highest drive strength.
Bit 13 gpio7_oen — This bit configures GPIO7 as an output. 1 = GPIO7 enabled as output.
0 = GPIO7 disabled as output.
Bit 12 gpio6_oen — This bit configures GPIO6 as an output. 1 = GPIO6 enabled as output.
0 = GPIO6 disabled as output.
Bit 11 gpio5_oen — This bit configures GPIO5 as an output. 1 = GPIO5 enabled as output.
0 = GPIO5 disabled as output.
Bit 10 gpio4_oen — This bit configures GPIO4 as an output. 1 = GPIO4 enabled as output.
0 = GPIO4 disabled as output.
Bit 9 gpio3_oen — This bit configures GPIO3 as an output. 1 = GPIO3 enabled as output.
0 = GPIO3 disabled as output.
Bit 8 gpio2_oen — This bit configures GPIO2 as an output. 1 = GPIO2 enabled as output.
0 = GPIO2 disabled as output.
Bit 7 gpio1_oen — This bit configures GPIO1 as an output. 1 = GPIO1 enabled as output.
0 = GPIO1 disabled as output.
Bit 6 gpio7_ien — This bit configures GPIO7 as an input. 1 = GPIO7 enabled as input.
0 = GPIO7 disabled as input.
Bit 5 gpio6_ien — This bit configures GPIO6 as an input. 1 = GPIO6 enabled as input.
0 = GPIO6 disabled as input.