GlobalSat ET-332 User Manual

環天衛星科技股份有限公司

PRODUCT USER MANUAL

GPS ENGINE BOARD

ET-332

GlobalSat Technology Corporation

台北縣中和市建一路

16, No.186,Chien 1 Road, 235Chung Ho City,Taipei Hsien, Taiwan ,R.O.C.

186號16樓(

遠東世紀廣場

)

Tel: [phone](Rep.) Fax: [phone]
Web: www.globalsat.com.tw E-mail: [e-mail]

Features:

SiRF starⅢ high performance GPS Chip Set
Very high sensitivity (Tracking Sensitivity: -159 dBm)
Extremely fast TTFF (Time To First Fix) at low signal level
Compact size (40.5mm * 35 mm * 10mm) suitable for space-sensitive application
Support NMEA 0183 and SiRF binary protocol
Build-in SuperCap to reserve system data for rapid satellite acquisition.
Cold start under 40 seconds, average
Hot start under 1 seconds, average

Specification:

General

Chipset SiRF StarⅢ
Frequency L1, 1575.42 MHz
C/A code 1.023 MHz chip rate
Channels 20 channel all-in-view tracking
Sensitivity -159 dBm

Accuracy

Position 10 meters, 2D RMS
5 meters, 2D RMS, WAAS enabled
Velocity 0.1 m/s
Time 1us synchronized to GPS time

Datum

Default WGS-84

Acquisition Time

Reacquisition 0.1 sec., average
Hot start 1 sec., average
Warm start 38 sec., average
Cold start 42 sec., average

Dynamic Conditions

Altitude 18,000 meters (60,000 feet) max
Velocity 515 meters /second (1000 knots) max

Acceleration Less than 4g
Jerk 20m/sec **3

Power

Main power input 3.8V ~ 6.5V DC input
Power consumption 75mA (Continuous mode)
30mA (Trickle power mode)

Interface

Baud rate 4,800 to 57,600 bps adjustable
Output message SiRF binary or

NMEA 0183 GGA, GSA, GSV, RMC, VTG, GLL

Environmental

Operating Temp -40℃ to +85℃

Physical Characteristics

Interface Connection

* Pin-out of the 12-pin interface conne ctor

Pin
Number Name

1

2

3

4

5

6

7

VBAT

GND

VDC

PBRES

GPIO1

TXA

RXA

Description

Ground

Backup Battery

3.8V~5.5V DC Power Input

Push Button Reset Input (Active Low) Input

(Reserved)

Serial Data Output A (GPS Data)

Serial Data Input A (Command)

Type

Input

Input

Output

Input

8

9

10

11

12

TIMEMARK

GND

GND

SELECT

GND

Ground

Ground

(Reserved)

1PPS Time Mark Output

Ground

Interface description

* VDC (DC power input):

This is the main DC supply for a 3.8V ~ 5.5V power module board.

* VBAT (Backup battery):

Output

This is the battery backup input that powers the SRAM and RTC when main
power is removed .Typical current draw is 10uA. Without an external backup battery,
the module/engine board will execute a cold star after every turn on. To achieve the

faster start-up offered by a hot or warm start, a battery backup must be connected. To
maximize battery lifetime, the battery voltage should be between 2.5v and 3.6v.

* PBRES (Push button reset):

This pin provides an active-low reset input to the engine board. It causes the
engine board to reset and start searching for satellites.

* SELECT :

Do not connect.

* TXA :

This is the main transmits channel for outputting navigation and measurement
data to user’s navigation software or user written software.
Output TTL level , 0V ~ 2.85V

* RXA :

This is the main receive channel for receiving software commands to the engine
board from SiRFdemo software or from user written software.
Normally this pin must be kept in high, and if you don’t use this pin please
connect a resistor to pull high.

* Time mark :

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

synchronized to GPS time.

* GND :

GND provides the ground for the engine board. Connect all grounds.