Table of Contents
Advertisement
■ Display Circuit
The CPU (IC6) controls the display LEDs. When the trans-
ceiver is busy, the LEDG line goes high, Q4 turns on and the
green LED (D11) lights. In transmit mode, the LEDR line
goes high, Q8 turns on and the red LED (D12) lights. Backlit
LEDs (D1~D4) are provided.
When a function key (MON, PF, C1, C2, C3 or C4) is se-
lected, its respective line goes high (LED MON, LED PF,
LED C1, LED C2, LED C3 or LED C4), the switch connected
to that line turns on and the amber LED lights.
■ Key Matrix Circuit
The TK-7108 front panel has function keys. Each of them
is connected to a cross point of a matrix of the KMI1 to
KMO2 ports of the microprocessor. The KMO1 to KMO2
ports are always high, while the KMI1 to KMI4 ports are al-
ways low.
The microprocessor monitors the status of the KMI1 to
KMO2 ports. If the state of one of the ports changes, the
microprocessor assumes that the key at the matrix point
corresponding to that port has been pressed.
CIRCUIT DESCRIPTION / 电路说明
LEDMON
LEDPF
LEDC1
LEDC2
LEDC3
LEDC4
LEDG
LEDR
MICBL
Fig. 12 Display circuit / 图12 显示电路
KMI1
KMI2
KMI3
IC6
KMI4
CPU
KMO2
KMO1
Fig. 13 Key matrix circuit / 图13 按键矩阵电路
■ 显示电路
CPU (IC6) 控制显示指示灯。当通信机繁忙，LEDG线为高电
平时，Q4导通并且绿色指示灯 (D11) 点亮。在发射模式中，
LEDR线为高电平，Q8导通并且红色指示灯 (D12) 点亮。提供
背景灯光指示灯 (D1至D4)。
当一个功能键（MON、PF、C1、C2、C3和C4)被选择时，
它相应的线路进入高电平(LED MON、LED PF、LED C1、LED
C2、LED C3 or LED C4), 与该线路相连的开关接通并且琥珀色
显示灯点亮。
Q1
SW
D5
Q5
SW
D6
Q2
SW
D7
Q6
SW
D8
Q3
SW
D9
Q7
SW
D10
Q4
SW
D11
Q8
SW
D12
Q10
Q9
SW
SW
D1~4
■ 按键矩阵电路
TK-7108 的前端面板有功能键。每一个按键被连接到微处理
器的 KMI1 到 KMO2 端口矩阵的一个交叉点。当 KMI1 到 KMI4
端口通常为低电平时，KMO1 到 KMO2 端口通常为高电平。
微处理器监听 KMI1 到 KMO2 端口的状态。如果其中一个端
口的状态发生了变化， 微处理器认定对应于此端口的在矩阵点
的按键已被按下。
TK-7108
21
Advertisement
Table of Contents
