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S3C2501X
I/O PORTS
12-1
12
I/O PORTS
12.1 OVERVIEW
S3C2501X 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.
I/O Ports
= Pad Ports
(or PP)
Function's Port
GPIO
Input Mode
Output Mode
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'.
12.2 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
•
7 UART Signals
NOTE
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 stay high, and fall back to low.)
Summary of Contents for S3C2501X
Page 18: ......
Page 275: ...MEMORY CONTROLLER S3C2501X 5 60 NOTES ...
Page 289: ...I2C CONTROLLER S3C2501X 6 14 NOTES ...
Page 373: ...GDMA CONTROLLER S3C2501X 9 24 NOTES ...
Page 435: ...I O PORTS S3C2501X 12 12 NOTES ...