Table of Contents
Advertisement
S3C2500B
15
15.1 OVERVIEW
S3C2500B has 64 programmable I/O ports. I/O port function control registers (IOPCON2: upper word, IOPCON1:
lower word) select either function's port or GPIO. If IOPCON1/2 register is set to GPIO, IOPMODE1/2 register
should be set to either input mode or output mode.
For example, if you select IOPCON1/2 for GPIO and IOPMODE1/2 for input, then I/O port can be used for GPIO
input mode. When the value is latched in IOPDATA1/2 register, CPU can read IOPDATA1/2 register value. If you
select IOPCON1/2 for GPIO and IOPMODE1/2 for output, then CPU can write the data to IOPDATA1/2 register
and the value can be transferred to the output port.
If you select IOPCON1[14] for xGDMA Req[0], then the port is used for GDMA Req port mode. I/O port signal
decision register (IOPGDMA) is used when IOPCON1 is selected for GDMA Req/Ack. IOPGDMA controls
external GDMA Req/Ack signals.
IOPEXTINTPND register is used for external interrupt status. IOPEXTINTPND is set when external interrupt is
generated and is cleared when IOPEXTINTPND register is re-written to '1'.
15.2 FEATURES
•
64 Programmable I/O Ports
•
Configurable to Input, Output, or I/O Mode for Dedicated Signals
•
6 External Interrupt Requests
•
4 External GDMA Requests
•
4 External GDMA Acknowledges
•
6 Timer Outputs
•
22 HDLC Signals
•
14 UART Signals
PP[27] - PP[18] ports support external software reset. When PP[27:18] are in GPIO output mode and
when nRESET or system reset (including watchdog reset) is asserted, the external devices that are
connected to PP[27:18] are also reset. (That is, the output signals go low, and rise back to high.)
I/O PORTS
I/O Ports = Pad Ports (or PP)
Function's Port
GPIO
Input Mode
Output Mode
NOTE
I/O PORTS
15-1
Advertisement
Table of Contents
