Samsung S3C2440A User Manual
Page 25
PRODUCT OVERVIEW
S3C2440A RISC MICROPROCESSOR
1-24
Table 1-3. S3C2440A Signal Descriptions (Sheet 4 of 6)
Signal Input/Output
Description
SPI
SPIMISO[1:0]
IO
SPIMISO is the master data input line, when SPI is configured as a master.
When SPI is configured as a slave, these pins reverse its role.
SPIMOSI[1:0]
IO
SPIMOSI is the master data output line, when SPI is configured as a master.
When SPI is configured as a slave, these pins reverse its role.
SPICLK[1:0] IO
SPI
clock
nSS[1:0]
I
SPI chip select(only for slave mode)
SD
SDDAT[3:0]
IO
SD receive/transmit data
SDCMD
IO
SD receive response/ transmit command
SDCLK O
SD
clock
General Port
GPn[129:0]
IO
General input/output ports (some ports are output only)
TIMMER/PWM
TOUT[3:0] O
Timer
output[3:0]
TCLK[1:0]
I
External timer clock input
JTAG TEST LOGIC
nTRST
I
nTRST(TAP Controller Reset) resets the TAP controller at start.
If debugger is used, A 10K pull-up resistor has to be connected.
If debugger(black ICE) is not used, nTRST pin must be issued by a low active
pulse(Typically connected to nRESET).
TMS
I
TMS (TAP Controller Mode Select) controls the sequence of the TAP
controller's states. A 10K pull-up resistor has to be connected to TMS pin.
TCK
I
TCK (TAP Controller Clock) provides the clock input for the JTAG logic.
A 10K pull-up resistor must be connected to TCK pin.
TDI
I
TDI (TAP Controller Data Input) is the serial input for test instructions and data.
A 10K pull-up resistor must be connected to TDI pin.
TDO
O
TDO (TAP Controller Data Output) is the serial output for test instructions and
data.