III PERIPHERAL BLOCK: INPUT/OUTPUT PORTS

CFEX0: P12, P14 function extension (D0) / Port function extension register (0x402DF)

CFEX1: P10, P11, P13 function extension (D1) / Port function extension register (0x402DF)

CFEX2: P21 function extension (D2) / Port function extension register (0x402DF)

CFEX3: P31 function extension (D3) / Port function extension register (0x402DF)

CFEX4: P04 function extension (D4) / Port function extension register (0x402DF)

CFEX5: P05 function extension (D5) / Port function extension register (0x402DF)

Sets whether the function of an I/O-port pin is to be extended.

Write "1": Function-extended pin

Write "0": I/O-port/peripheral-circuit pin

Read: Valid

Writing "1" to a CFEXx bit configures the corresponding pin(s) for extended I/O operation. Otherwise, the corresponding CFPx pin takes effect. Always write "0" to CFEX4 and CFEX5.

At cold start, CFEX0 and CFEX1 are set to "1" (function-extended pin) and other bits are set to "0" (I/O- port/peripheral-circuit pin). At hot start, CFEX retains its state from prior to the initial reset.

B-III-9-10

EPSON

S1C33210 FUNCTION PART