Sharp R-1880LS Service Manual page 36

R-1880LS/LST
Pin No. Signal
3 VSS
33 P7
34 P6
35 P5
36 P4
37-40 P3-P0
41-44 P17-P14
45-48 P13-P10
49 P07
50 P06
51 P05
5 P04
53 P03
54 P0
55 P01
I/O
Output to control oscillation input of XIN.
Power source voltage:-5V.
IN
VC voltage of power source circuit input.
Signal coming from touch key.
IN
When any one of G1 line keys on key matrix is touched, a corresponding signal will be input
into P7. When no key is touched, the signal is held at "L" level.
Signal similar to AN1.
IN
When any one of G11 line keys on key matrix is touched, a corresponding signal will be input
into P6.
Signal similar to P27.
IN
When any one of G10 line keys on key matrix is touched, a corresponding signal will be input
into P5.
Signal similar to P27.
IN
When any one of G9 line keys on key matrix is touched, a corresponding signal will be input
into P4.
Digit selection signal.
OUT
The relationship between digit signal and digit are as fol-
lows;
Digit signal
P14 . ................................ 1st.
P15 . ...............................nd.
P16 . ............................... 3rd.
P17 . ................................4th.
(ß : INTO signal)
Refer to the touch control panel circuit about the relation
between signals and digits. Normally, one pulse is output
in every synchronized signal (ß) period, and input to the grid
of the fluorescent display.
Digit selection signal.
OUT
Segment data signal.
OUT
Segment data signal.
OUT
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
while one of G7 line keys on key matrix is touched.
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
while one of G6 line keys on key matrix is touched.
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
while one of G5 line keys on key matrix is touched.
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
while one of G4 line keys on key matrix is touched.
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
while one of G3 line keys on key matrix is touched.
Segment data signal.
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to AN1 and P7 - P4 terminal
Description
Digit Digit signal Digit
P0 ................................5th.
P1 ................................6th.
P ................................7th.
P3 ................................8th.
Signal similar to P3.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
Signal similar to P55.
36
§(60Hz)
GND
P14
VP
P15
P16
P17
P20
P21
P22
P23
H
L