Service manual

19
R-204EWA
DESCRIPTION OF LSI
The I/O signal of the LSI are detailed in the following table.
Pin No. Signal I/O Description
1 RESET 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.
2 TEST IN Connected to GND.
3 VSS IN Power source voltage: -5V.
VSS voltage of power source circuit input. Connected to VC.
4 OCS3 IN Internal clock oscillation frequency setting input.
The internal clock frequency is set by inserting the resistor oscillation circuit with
respect to OCS4 terminal.
5 OCS4 OUT Internal clock oscillation frequency control output.
Output to control oscillation input of OCS3.
6 VD1 IN Power source for oscillation circuit.
7 VDD IN Power source voltage input terminal.
Connected to GND.
8 AVDD IN A/D converter power source voltage.
The power source voltage to drive the A/D converter in the LSI. Connected to GND.
9 AVREF IN A/D converter power source voltage.
The power source voltage to drive the A/D converter in the LSI. Connected to GND.
10 AVSS IN Power source voltage: -5V.
AVSS voltage of power source circuit input. Connected to VC.
11-13 P40-P42 IN Terminal to change functions according to the Model.
By using the A/D converter contained in the LSI, DC voltage in accordance with the
Model in operation is applied to set up its function.
14 P43 IN To input signal which communicates the door open/close information to LSI.
Door close “H” level signal (0V). Door open “L” level (-5V).
15 BZ OUT Signal to sound buzzer (2.0 kHz).
A: key touch sound.
B: Completion sound.
16 R00 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G6 line keys on key matrix is touched.
17 R01 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G5 line keys on key matrix is touched.
18 R02 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G4 line keys on key matrix is touched.
19 R03 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G3 line keys on key matrix is touched.
20 P20 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G2 line keys on key matrix is touched.
21 P21 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P23, K00, K01 and K02
terminal while one of G1 line keys on key matrix is touched.
22 P22 OUT Terminal not used.
A
B
0.1 sec.
2.0 sec.
H : GND
L : -5V
H : GND
L : -5V