Preliminary
I/O PORTS
S3C2451X RISC MICROPROCESSOR
11-32
PORT M CONTROL REGISTERS (GPMCON, GPMDAT, GPMUDP)
Register Address
R/W
Description
Reset
Value
GPMCON
0x56000100
R/W
Configures the pins of port M
0xA
GPMDAT
0x56000104
R
The data register for port M
0x0
GPMUDP 0x560000108
R/W
pull-up/down
control register for port M
0x0
Reserved 0x56000010c –
–
–
GPMCON Bit
Description
Reserved [31:4]
Reserved
GPM1
[3:2]
Others = GPM Input
10 = FRnB
GPM0
[1:0]
Others = GPM Input
10 = RSMBWAIT
GPMDAT Bit
Description
Reserved [31:2]
Reserved
GPM[1:0]
[1:0]
When the port is configured as an input port, the corresponding bit is the
pin state
When the port is configured as functional pin, the undefined value will be
read.
GPMUDP
Bit
Description
Reserved [31:6]
Reserved
nWAIT [5:4]
[CPU:CPD]
00 : pull-up/down disable 01 : pull-down enable
10 : pull-up enable 11 : not-available
GPMUDP1 [3:2]
[CPU:CPD]
00 : pull-up/down disable 01 : pull-down enable
10 : pull-up enable 11 : not-available
GPMUDP0 [1:0]
[CPU:CPD]
00 : pull-up/down disable 01 : pull-down enable
10 : pull-up enable 11 : not-available