– 57 –
Pin No.
Pin Name
I/O
Description
47
SS SPI EN
O
Enable signal output to the RF unit (RF201) “L” active
48
SP/HS SELECT
O
Speaker/local handset selection signal output “L”: local handset, “H”: speaker
49
WDT
I
Watch dog timer reset signal input terminal “H”: reset Not used (fixed at “L”)
50
RING DET
I
Detection signal input of the ringer coming “L”: ringer coming
51
AC POWER FAIL
I
Power fail detection signal input “L”: power fail
52
SS IRQ
I
Interrupt request signal input from the RF unit (RF201) “L” active
53
RESET
I
System reset signal input from the reset signal generator (IC253) “L”: reset
For several hundreds msec. after the power supply rises, “L”: is input, then it changes to “H”
54
XT1
I
Sub system clock input terminal (32.768 kHz) Not used (fixed at “H”)
55
XT2
O
Sub system clock output terminal (32.768 kHz) Not used (open)
56
VSS1
—
Ground terminal
57
CF1
I
Main system clock input terminal (6 MHz)
58
CF2
O
Main system clock output terminal (6 MHz)
59
VDD1
—
Power supply terminal (+5V)
60
BRANCH DET
(ON)
I
Line voltage detection signal input at the hook on (A/D input)
(Used for the SPP-S2430 model)
61
BRANCH DET
(OFF)
I
Line voltage detection signal input at the hook off (A/D input)
62
AN2
I
Not used (open)
63
LCD CS
O
Chip select signal output to the liquid crystal display module (LCD101) “L” active
64
LCD SDA
I/O
Two-way data bus with the liquid crystal display module (LCD101)
