Sharp R-21JV-F Service Manual page 22

R-21HT-F
R-21JV-F
Pin No. Signal
22-24 P44-P42 OUT
25 INT1
26 P40
27 RESET
28 P71 OUT
29 P70 IN/OUT
30 XIN
31 XOUT OUT
32 VSS
33 P27
34 P26
35 P25
36 P24
37-38 P23-P22 OUT
39-40 P21-P20 OUT
41-48 P17-P10 OUT
49-56 P07-P00 OUT
57-59 P37-P35 OUT
60 P34 OUT
I/O
Digit selection signal.
IN Signal synchronized with commercial power source frequency.
This is basic timing for all time processing of LSI.
IN Connected to GND through resistor.
IN Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is supplied. Temporarily
set to "L" level the moment power is supplied, at this time the LSI is reset. Thereafter
set at "H" level.
Memory (EEPROM) clock output.
Memory (EEPROM) data input/output.
IN Internal clock oscillation frequency setting input.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with
respect to XOUT terminal.
Internal clock oscillation frequency control output.
Output to control oscillation input of XIN.
IN Connected to GND.
IN Signal coming from touch key.
When either one of G-12 line keys on key matrix is touched, a corresponding signal
out of P30, P31, P32, P33, P34 will be input into P27. When no key is touched, the
signal is held at "L" level.
IN Signal similar to P27.
When either one of G-11 line keys on key matrix is touched, a corresponding signal
will be input into P26.
IN Signal similar to P27.
When either one of G-10 line keys on key matrix is touched, a corresponding signal
will be input into P25.
IN Signal similar to P27.
When either one of G-9 line keys on key matrix is touched, a corresponding signal
will be input into P24.
Terminal not used.
Segment data signals.
The relation between signals and indicators are as follows:
Signal Segment
P21,P20 .......... 1
P17.P16 .......... 2
P15,P14 .......... 3
P13,P12 .......... 4
P11,P10 .......... 5
P07,P06 .......... 6
Segment data signal.
Signal similar to P21.
Segment data signal.
Signal similar to P21.
Terminal not used.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27, P26, P25 and P24
terminals while one of G4 line keys on key matrix is touched.
Description
Signal similar to P45.
Signal Segment
P05,P04 ......... 7
ß(60Hz)
P03,P02 ......... 8
P01,P00 ......... 9
20
H : +5V
L : GND
16.7 msec
+5V
GND