Sharp R-1482 Service Manual page 25

Pin No. Signal I/O
22 P44 OUT
23 P43 OUT
24 P42 IN
25 INT1 IN
26 P40 IN
27 RESET IN
28-29 P71-P70 OUT
30 XIN IN
31 XOUT OUT
32 VSS IN
33 P27 IN
34 P26 IN
35 P25 IN
36 P24 IN
37-40 P23-P20 OUT
Terminal not used.
Signal to sound buzzer.
A: key touch sound.
B: Completion sound.
C: When the temperature of the oven cavity reaches
the preset temperature in the preheating mode,
or when the preheating hold time (30 minutes) is
elapsed.
Terminal not used.
Signal to synchronize LSI with commercial power source frequency.
This is the basic timing for all real time processing of LSI.
Connected to VC.
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 terminal.
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 G12 line keys on key matrix is touched, a corresponding signal 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 G11 line keys on key matrix is touched, a corresponding signal will be
input into P26.
Signal similar to P27.
When any one of G10 line keys on key matrix is touched, a corresponding signal will be
input into P25.
Signal similar to P27.
When any one of G9 line keys on key matrix is touched, a corresponding signal will be input
into P24.
Digit selection signal.
The relationship between digit signal and digit are as follows;
Digit signal .................................. Digit
P14 ................................................ 1st.
P15 ............................................... 2nd.
P16 ............................................... 3rd.
P17 ................................................ 4th.
P20 ................................................ 5th.
P21 ................................................ 6th.
P22 ................................................ 7th.
P23 ................................................ 8th.
(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.
23
Description
A
B
1 sec
C
ß(60Hz)
P14
P15
P16
P17
P20
P21
P22
P23
R-1480
R-1481
R-1482
0.1 sec
2 sec
1 sec
H: GND
L
H : GND
L (-5V)
16.7 msec
H
L
GND
VP