Sharp R-990KS Service Manual page 22

R990K(W)
Pin No. Signal I/O
25 INT1 IN
26 P40 IN
27 RST IN
28/29 XCIN/XCOUT OUT
30 XIN IN
31 XOUT OUT
32 VSS IN
33 P27 IN
34 P26 IN
35 P25 IN
36 P24 IN
37 P23 OUT
38-40 P22-P20 OUT
41 P17 OUT
42 P16 OUT
43 P15 OUT
44 P14 OUT
45 P13 OUT
46 P12 OUT
Signal to synchronize LSI with commercial power source freqency.
This is the basic timing for all real time processing of LSI.
Connected to GND.
Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied. Temporarily set to "L" level the moment
power is applied, at this time the LSI is reset. Thereafter set at "H" level.
Terminal not used.
Internal clock oscillation frequency setting input.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect to XOUT termi-
nal.
Internal clock oscillation frequency control output.
Output to control oscillation input of XIN.
Power source voltage: -5V.
VC voltage of power source circuit input.
Signal coming from touch key.
When any one of G-1 line keys on key matrix is touched, a corresponding signal from P17 - P17 will be input
into P27. When no key is touched, the signal is held at "L" level.
Signal similar to P27.
When any one of G-2 line key on key matrix is touched, a corresponding signal will be input into P26.
Signal similar to P27.
When any one of G-3 line key on key matrix is touched, a corresponding signal will be input into P25.
Signal similar to P27.
When any one of G-4 line key on key matrix is touched, a corresponding signal will be input into P24.
Segment data signals.
The relation between signals and indicators are as follows:
Signal Segment Signal
P23...............P1 P17...............P5
P22...............P2 P16...............P6
P21...............P3 P15...............P7
P20...............P4 P14...............P8
Segment data signal.
Signal similar to P23.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-12 line keys on
key matrix is touched.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-11 line keys on
key matrix is touched.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-10 line keys on
key matrix is touched.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-9 line keys on
key matrix is touched.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-8 line keys on
key matrix is touched.
Segment data signal.
Signal similar to P23.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P24-P27 terminal while one of G-7 line keys on
key matrix is touched.
Description
Segment Signal Segment
P13...............P9
P12.............P10
P11.............P11
P10.............P12
9 – 3
H : GND
L (-5V)
20 msec.
Signal Segment
P07.............P13
P06.............P14
P05.............P15
P04.............P16