HYT POWER446, Руководство по обслуживанию

Страница: 14 / 61

POWER446 Service Manual
12
6. MCU Control Section
Channel SW
MB95F108AK
WPFV-GE1
U605
PTT
MON
BAT
A T 2 4 C 6 4
U609
APC/TUNE
PLL
1.vox
2.BUSY_DET
8.UART
7.W/N
6.DC/CTC
5.SAVE
4.T/R
3.BEEP/CALL
X601
9.BAT_DET
U610
Reset
IC
10.PLL_LD
7.3728M 晶体
Figure 8
MCU operates at the clock frequency of 7.3728MHz. The MCU control circuit is mainly composed of
MCU, EEPROM, reset IC, keys and knobs etc. This section has the following functions:
1. Signal Control:
To control Battery Save Mode;
To control narrow band;
To control TX/RX switch;
To control APC/TUNE output voltage;
To control power supply of transmitter and audio amplifier;
To control SQL Off detection.
2. Signal Detect:
To detect startup of external PTT, MONI and VOX;
To detect PLL Unlock;
To detect VOX ON level;
To detect low battery alert;
To detect and determine external earpiece.
3. Data Transfer and Process:
To initialize EEPROM data;