10

4890AS–GPS–09/05

ATR0621 [Preliminary]

3.3

Setting GPSMODE0 to GPSMODE12

The start-up configuration of a ROM-based system without external non-volatile memory is

defined by the status of the GPSMODE pins after system reset. Alternatively, the system can

be configured through message commands passed through the serial interface after start-up.

If Flash memory is available, configuration data can be stored in Flash memory. If EEPROM

memory is connected, configuration data can be stored in EEPROM. Default designates set-

tings used by ROM firmware if GPSMODE configuration is disabled (GPSMODE0 =0).

3.3.1

Enable GPSMODE Pin Configuration

3.3.2

Sensitivity Settings

Table 3-3.

GPSMODE Functions

Pin

Function

GPSMODE0

Enable configuration with GPSMODE pins

GPSMODE1

This pin is used for FixNow functionality and not used for GPSMODE configuration

GPSMODE2

GPS sensitivity settings

GPSMODE3

GPSMODE4

This pin (NAADET1) is used as active antenna supervisor input and not used for

GPSMODE configuration

GPSMODE5

Serial I/O configuration

GPSMODE6

GPSMODE7

USB Power Mode

GPSMODE8

General I/O Configuration

GPSMODE9

This pin (NAADET0) is used as active antenna supervisor input and not used for

GPSMODE configuration

GPSMODE10

General I/O Configuration

GPSMODE11

GPSMODE12

Serial I/O configuration

Table 3-4.

Enable Configuration with GPSMODE Pins

GPSMODE0

(Reset = PD) Description

0

Ignore all GPSMODE pins. The default settings as indicated below are used

1

Use settings as specified with GPSMODE[2, 3, 5 to 8, 10 to12]

Table 3-5.

GPS Sensitivity Settings

GPSMODE3

(Fixed PU)

GPSMODE2

(Reset = PU) Description

0

0

Auto mode

0

1

Fast mode

1

0

Normal mode (Default)

1

1

High sensitivity