8 UNIVERSAL PORT MULTIPLEXER (UPMUX)
8-2
Seiko Epson Corporation
S1C31D50/D51 TECHNICAL MANUAL
(Rev. 2.00)
8.3 Control Registers
P
xy–xz
Universal Port Multiplexer Setting Register
Register name
Bit
Bit name
Initial
Reset
R/W
Remarks
UPMUXPxMUXn
15–13 PxzPPFNC[2:0]
0x0
H0
R/W –
12–11 PxzPERICH[1:0]
0x0
H0
R/W
10–8 PxzPERISEL[2:0]
0x0
H0
R/W
7–5 PxyPPFNC[2:0]
0x0
H0
R/W
4–3 PxyPERICH[1:0]
0x0
H0
R/W
2–0 PxyPERISEL[2:0]
0x0
H0
R/W
*
1: ‘x’ in the register name refers to a port group number and ‘n’ refers to a register number (0–3).
*
2: ‘x’ in the bit name refers to a port group number, ‘y’ refers to an even port number (0, 2, 4, 6), and ‘z’ refers to an
odd port number (z = y + 1).
Bits 15–13 P
xz
PPFNC[2:0]
Bits 7–5
P
xy
PPFNC[2:0]
These bits specify the peripheral I/O function to be assigned to the port. (See Table 8.3.1.)
Bits 12–11 P
xz
PERICH[1:0]
Bits 4–3
P
xy
PERICH[1:0]
These bits specify a peripheral circuit channel number. (See Table 8.3.1.)
Bits 10–8 P
xz
PERISEL[2:0]
Bits 2–0
P
xy
PERISEL[2:0]
These bits specify a peripheral circuit. (See Table 8.3.1.)
Table 8.3.1 Peripheral I/O Function Selections
UPMUXPxMUXn.
PxyPPFNC[2:0] bits
(Peripheral I/O
function)
UPMUXPxMUXn.PxyPERISEL[2:0] bits (Peripheral circuit)
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
None
*
I2C
SPIA
UART3
T16B
Reserved
Reserved
Reserved
UPMUXPxMUXn.PxyPERICH[1:0] bits (Peripheral circuit channel)
–
0x0–0x2
0x0–0x2
0x0–0x2
0x0–0x1
–
–
–
–
Ch.0–2
Ch.0–2
Ch.0–2
Ch.0–1
–
–
–
0x0
None
*
None
*
None
*
None
*
None
*
None
*
None
*
None
*
0x1
Reserved
SCLn
SDIn
USINn
TOUTn0/
CAPn0
Reserved
Reserved
Reserved
0x2
SDAn
SDOn
USOUTn
TOUTn1/
CAPn1
0x3
Reserved
SPICLKn
Reserved
TOUTn2/
CAPn2
0x4
#SPISSn
TOUTn3/
CAPn3
0x5
Reserved
Reserved
0x6
0x7
*
“None” means no assignment. Selecting this will put the Pxy pin into Hi-Z status when peripheral I/O function 1 is
selected and enabled in the I/O port.
Note: Do not assign a peripheral input function to two or more I/O ports. Although the I/O ports output
the same waveforms when an output function is assigned to two or more I/O port, a skew oc-
curs due to the internal delay.