9 i/O PORTS (P)
S1C17624/604/622/602/621 TeChniCal Manual
Seiko epson Corporation
9-21
P4[3:0] Port Function Select Register (P40_43PMuX)
Register name address
Bit
name
Function
Setting
init. R/W
Remarks
P4[3:0] Port
Function Select
Register
(P40_43PMuX)
0x52a8
(8 bits)
D7–6 P43MuX[1:0] P43 port function select
P43MUX[1:0]
Function
0x0 R/W
0x3
0x2
0x1
0x0
reserved
reserved
P43
DCLK
D5–4 P42MuX[1:0] P42 port function select
P42MUX[1:0]
Function
0x0 R/W
0x3
0x2
0x1
0x0
reserved
reserved
P42
DST2
D3–2 P41MuX[1:0] P41 port function select
P41MUX[1:0]
Function
0x0 R/W
0x3
0x2
0x1
0x0
reserved
reserved
P41
DSIO
D1–0 P40MuX[1:0] P40 port function select
P40MUX[1:0]
Function
0x0 R/W
0x3
0x2
0x1
0x0
reserved
reserved
FOUTH
P40
The P40 to P43 port pins are shared with the peripheral module pins. This register is used to select how the pins are
used.
D[7:6]
P43MuX[1:0]: P43 Port Function Select Bits
0x3 (R/W): Reserved
0x2 (R/W): Reserved
0x1 (R/W): P43
0x0 (R/W): DCLK (DBG) (default)
P43 is an output-only port and no external signal cannot be input.
To use P43 as a general-purpose output port, make the following settings:
1. Set P4OEN3/P4_OEN register to 1 (output).
2. Set P43MUX[1:0] to 0x1 (P43).
When the P43 output port is not used (or used as the DCLK port), make the following settings:
1. Set P43MUX[1:0] to 0x0 (DCLK).
2. Set P4OEN3 to 0 (input).
D[5:4]
P42MuX[1:0]: P42 Port Function Select Bits
0x3 (R/W): Reserved
0x2 (R/W): Reserved
0x1 (R/W): P42
0x0 (R/W): DST2 (DBG) (default)
D[3:2]
P41MuX[1:0]: P41 Port Function Select Bits
0x3 (R/W): Reserved
0x2 (R/W): Reserved
0x1 (R/W): P41
0x0 (R/W): DSIO (DBG) (default)
D[1:0]
P40MuX[1:0]: P40 Port Function Select Bits
0x3 (R/W): Reserved
0x2 (R/W): Reserved
0x1 (R/W): FOUTH (CLG)
0x0 (R/W): P40 (default)