Globalsat EM-506 [5/17] Operating description

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Physical Characteristic

OPERATING Description

GND

This is Ground pin for the baseband circuit.

VIN

This is the main power supply to the engine board. (3.1Vdc to 3.5Vdc)

RXD

This is the main channel for receiving software commands from SiRFdemo software or from your

proprietary software.

TXD

This is the main transmits channel for outputting navigation and measurement data to user’s

navigation software or user written software. Output is TTL level, 0V ~ 2.85V.

VBAT

This is the battery backup power input for the SRAM and RTC when main power is off. Without the

external backup battery, EM-506 will always execute a cold star after turning on. To achieve the

faster start-up offered by a hot or warm start, a battery backup must be connected. The battery

voltage should be between 2.0V and 3.5V.

1PPS

This pin provides one pulse-per-second output from the engine board that is synchronized to GPS

time.

LED

LED indicator for GPS fix or not fix

LED OFF: Receiver switch off

LED ON: No fixed, Signal searching

LED Flashing: Position Fixed