Icom IC-T90A Ctsel, Dtcs, Lcd, SEG35, SEG34, SEG31, CONT1, CONT0, SEG0, COM3, COM0, Volc, Beep

4-5-3 CPU (Continued)

Pin	Port	Description
number	name
		Outputs the 50 MHz modulation circuit
84	50M	control signal.
		Low: While 50 MHz is transmitting.
		Outputs the CT3 switch (LOGIC unit;
85	CTSEL	Q301) control signal.
		Low: DTCS/CTCSS is selected.
86	DTCS	Outputs the DTCS decorder filter con-
		trol signal.
88–90	SEG37–	Output segment data to	the	LCD
	SEG35	(LOGIC unit; DS4, pins 5–7).
92	SEG34	Outputs segment data to	the	LCD
		(LOGIC unit; DS4, pin 8).
94–96	SEG33–	Output segment data to	the	LCD
	SEG31	(LOGIC unit; DS4, pins 9–11).
97	CONT1	Output the LCD contrast control sig-
98	CONT0	nals.
99–127	SEG28–	Output segment data to	the	LCD
	SEG0	(LOGIC unit; DS4, pins 12–40).
128–131	COM3–	Output common data to the LCD
	COM0	(LOGIC unit; DS4, pins 1–4).
138	VOLC	Outputs the volume IC	(AF	unit;
		IC251, pin 5) control signal.
139	CTCOUT	Outputs CTCSS/DTCS signals.
141	BEEP	Output beep, DTMF tone, 1750 Hz
		tone sounds.
144	WXALT	Input port for the WX alert signal.

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