Samsung S3C2440A - Manual (Page 256)

I/O PORTS S3C2440A RISC MICROPROCESSOR
9-10
PORT B CONTROL REGISTERS(GPBCON, GPBDAT, GPBUP)
Register Address R/W Description Reset Value
GPBCON 0x56000010 R/W Configures the pins of port B 0x0
GPBDAT 0x56000014 R/W The data register for port B Undef.
GPBUP 0x56000018 R/W pull-up disable register for port B 0x0
Reserved 0x5600001c
PBCON Bit Description
GPB10 [21:20] 00 = Input 01 = Output
10 = nXDREQ0 11 = reserved
GPB9 [19:18] 00 = Input 01 = Output
10 = nXDACK0 11 = reserved
GPB8 [17:16] 00 = Input 01 = Output
10 = nXDREQ1 11 = Reserved
GPB7 [15:14] 00 = Input 01 = Output
10 = nXDACK1 11 = Reserved
GPB6 [13:12] 00 = Input 01 = Output
10 = nXBREQ 11 = reserved
GPB5 [11:10] 00 = Input 01 = Output
10 = nXBACK 11 = reserved
GPB4 [9:8] 00 = Input 01 = Output
10 = TCLK [0] 11 = reserved
GPB3 [7:6] 00 = Input 01 = Output
10 = TOUT3 11 = reserved
GPB2 [5:4] 00 = Input 01 = Output
10 = TOUT2 11 = reserved]
GPB1 [3:2] 00 = Input 01 = Output
10 = TOUT1 11 = reserved
GPB0 [1:0] 00 = Input 01 = Output
10 = TOUT0 11 = reserved
GPBDAT Bit Description
GPB[10:0] [10:0] When the port is configured as input port, the corresponding bit is the pin
state. When the port is configured as output port, the pin state is the same as
the corresponding bit. When the port is configured as functional pin, the
undefined value will be read.
GPBUP Bit Description
GPB[10:0] [10:0] 0: the pull up function attached to to the corresponding port pin is enabled.
1: the pull up function is disabled.