2-6 Notes For All Schematics and Circuit Boards
BL KP RED Red Keypad Back Light Control
BL LCD GREEN Green Display Back Light Control
BL LCD RED Red Display Back Light Control
BL RED Red Back Light Control
BOOT CNTRL Bootstrap Mode Enable Signal
BOOT MODE Boot Mode Select
BOOT PWR ON Control Head Switch On Signal
BOOT SCI RX Serial Communication Interface Receive Line
BOOT SCI TX Serial Communication Interface Transmit Line
BOOT VPP Boot Mode Select
BUS+ Bi-directional Serial Communication Line
BWSELECT Signal to select between the Ceramic Filter Pairs
CH ACT Channel Activity Indicator Signal (Fast Squelch)
CH KP ID Control Head Keypad ID (Data) Lines
CH REQUEST Control Head Request from Control Head µP
CLK Clock Signal
CNTLVLTG PA Power Control Voltage
CNTR AUDIO Audio Lines of the Controller
COL x Keypad Matrix Column x
CSX Chip Select Line PCIC / FRACN
DATA Data Signal
DC POWER ON Electronic Switching On or Off of the Radio's Voltage Regulators
DISCAUDIO Audio Output Signal from the Receiver IC
ECLK Clock (not used)
EE CS EEPROM Chip Select
EMERGENCY CONTROL Emergency Line to switch on the Radio's Voltage Regulators
EXP BD REQ Service Request Line from Expansion Board