User's Manual

12
MCU
SAVE
APC/TV
BATT Det
VOL Level
CH Encode
5TC
5RC
W/N
MUTE
T/R
BEEP
LED
AP SW I/E
RSSI
PTT
KEY SW
TXD/RXD
CTC/CDC Codec
E2PROM FLASH
AF Processor
PLL IC
RESET
Fig.6 MCU Block Diagram
Circuit in this section is mainly comprised of MCU, EEPROM, FLASH and reset IC etc.
MCU control circuit accomplishes the following functions: accomplish the reset
initialization according to the programmed feature of the radio when power on; detect
key signal and monitor battery voltage; send necessary frequency data to PLL
according to encode of the channel; switch and control transmit/receive according to
the signal input from PTT; turn on/off the mute circuit according to the input signaling
decode signal and squelch level signal; output control signal to control the light/off of
LED; output BEEP signal to drive the speaker.