Kenwood TH-K2AT, K2E, K2ET ■Key and Encoder Input Circuit, 16 key (K, K2, M, M2 and E3 types), 4 key (E type), Fig. 14 Key and Encoder input circuit

TH-K2AT/K2E/K2ET

CIRCUIT DESCRIPTION

■Key and Encoder Input Circuit

The POWER key is assigned to the interrupt port (pin 95) of the MPU.

The PTT key is assigned to the dedicated port (pins 13, 14) of the MPU.

Other keys composes a matrix and key presses are detected by scanning them by software.

The encoder reads data using the interrupt port (pins 35 and 36) of the MPU.

16 key (K, K2, M, M2 and E3 types)

						IC8
						MPU
KIN0	KIN1	KIN2	KIN3	KIN4		KOUT0 KOUT1 KOUT2 KOUT3 PWRSW PTTI		PTTE	ENCB	ENCA
						95	14	13	36	35
1	2	3	F		MENU
4	5	6	VFO		LAMP
7	8	9	MR		MONI
						POWER	S7
∗	0	#	CALL		SET	SW				ROTARY
										ENCODER
								J3
4 key (E type)
						IC8
						MPU
KIN0	KIN1	KIN2	KIN3	KIN4		KOUT0 KOUT1 KOUT2 KOUT3 PWRSW PTTI		PTTE	ENCB	ENCA
						95	14	13	36	35
F	VFO	MR	CALL		MENU
					LAMP
					MONI
						POWER	S7
					SET	SW				ROTARY
										ENCODER
								J3

Fig. 14 Key and Encoder input circuit

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