Sharp R-2397 service manual Pin No Signal Description, Auto clear terminal, Power source voltage

R-2397

Pin No.	Signal	I/O				Description
27	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.
28	XIN	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.
29	XOUT	OUT	Internal clock oscillation frequency control output.
			Output to control oscillation input of XIN.
30/31	XCIN/XCOUTIN/OUT		Terminal not used.
32	VSS	IN	Power source voltage: -5V.
			VC voltage of power source circuit input.
33	ø	OUT	Terminal not used.
34	R3	IN	Signal coming from touch key.
			When either one of G-12 line keys on key matrix is touched, a corresponding signal out
			of P11, P12, P14-P17 will be input into R3. When no key is touched, the signal is held at
			"L" level.
35	R2	IN	Signal similar to R3.
			When either one of G-11 line keys on key matrix is touched, a corresponding signal will
			be input into R2.
36	R1	IN	Signal similar to R3.
			When either one of G-10 line keys on key matrix is touched, a corresponding signal will
			be input into R1.
37	R0	IN	Signal similar to R3.
			When either one of G-9 line keys on key matrix is touched, a corresponding signal will
			be input into R0.
38	VP	IN	Anode (segment) of Fluorescent Display light-up voltage: -31V
			Vp voltage of power source circuit input.
39	P17	OUT	Segment data signal.
			The relation between signals and indicators are as follows:
			Signal	Segment	Signal	Segment
			P24	i	P13	f
			P23	j,k	P12	e	ß(50Hz)
			P17	LB	P11	d
								GND
			P16	UB	P10	c
			P15	h	P07	b		-31(V)
			P14	g	P06	a
			Key strobe signal.
			Signal applied to touch-key section. A pulse signal is input to R0-R3 terminal while one
			of G-6 line keys on key matrix is touched.
40	P16	OUT	Segment data signal.		Signal similar to P17.
			Key strobe signal.
			Signal applied to touch-key section. A pulse signal is input to R0-R3 terminal while one
			of G-5 line keys on key matrix is touched.
41	P15	OUT	Segment data signal.		Signal similar to P17.
			Key strobe signal.
			Signal applied to touch-key section. A pulse signal is input to R0-R3 terminal while one
			of G-4 line keys on key matrix is touched.
42-43	P14-P13	OUT	Segment data signal.
			Signal similar to P17.
44	P12	OUT	Segment data signal.		Signal similar to P17.
			Key strobe signal.
			Signal applied to touch-key section. A pulse signal is input to R0-R3 terminal while one
			of G-8 line keys on key matrix is touched.
45	P11	OUT	Segment data signal.		Signal similar to P17.
			Key strobe signal.
			Signal applied to touch-key section. A pulse signal is input to R0-R3 terminal while one
			of G-7 line keys on key matrix is touched.

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