
SYSTEM MANAGER
S3C3410X RISC MICROPROCESSOR
4-14
EXTERNAL DEVICE CONTROL REGISTERS (EXTCONn)
The S3C3410X can support the connection with two external I/O devices without any additional logic. It is very
cost effective, because the additional address decoding logic is not necessary. The smart connection between
S3C3410X and external I/O device can improve the cost, PCB size, and reliability of system. Differently from the
normal memory banks (8 memory banks in S3C3410X), S3C3410X defines the external I/O banks in SFR
(Special Function Register), EXTPORT, EXTDAT0, and EXTDAT1. EXTDAT0 and EXTDAT1 have 64 bytes
addressing region, respectively. To read the data from the external I/O device, you should execute the load
instruction by issuing the address (SFR start address + I/O bank offset), EXTPORT, EXTDAT0 or EXTDAT1.
Then, the data will be latched in the data register. To write the data into the external I/O device, you should
execute the store instruction by issuing the address (SFR start address + I/O bank offset), EXTPORT, EXTDAT0
or EXTDAT1. Then, the data will be written into the selected address, and the data will be written into the external
I/O device. These operation is automatically executed by the memory controller.
Register
Offset
Address
R/W
Description
Reset
Value
EXTCON0
0x2030
R/W
Extra device control register 0 (for external output port)
0x0
EXTCON1
0x2034
R/W
Extra device control register 1 (for external chip selection)
0x0
EXTCONx
Bit
Description
Initial State
DW
[1:0]
Data Bus Width: This bit determines the physical data bus width
for EXTBANKx (External bank0 and 1)
00 = Disable Bank
01 = 8-bit
10 = 16-bit
11 = Not used
00
Tcos
[4:2]
Set-up Time of nECS before nOE. Please refer the timing
diagram.
000 = 0 Clock
001 = 1 Clock
010 = 2 Clock
011 = 3 Clock
100 = 4 Clock
101 = 5 Clock
110 = 6 Clock
111 = 7 Clock
000
Tcoh
[10:8]
Hold Time of nECS after nOE. Please refer the timing diagram.
000 = 0 Clock
001 = 0 Clock
010 = 2 Clock
011 = 3 Clock
100 = 4 Clock
101 = 5 Clock
110 = 6 Clock
111 = 7 Clock
000
Tacc
[13:11]
Access Times (nOE low time)
000 = 0 Clock
001 = 2 Clock
010 = 3 Clock
011 = 4 Clock
100 = 5 Clock
101 = 6 Clock
110 = 7 Clock
111 = 8 Clock
000