3 setting gpsmode0 to gpsmode12, 1 enable gpsmode pin configuration – Rainbow Electronics ATR0635P1 User Manual

Page 12

4979D–GPS–06/08

ATR0635P1

3.3

Setting GPSMODE0 to GPSMODE12

The start-up configuration of this 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. This
configuration of the ATR0635P1 can be stored in an external non-volatile memory like
EEPROM. Default designates settings used by ROM firmware if GPSMODE configuration is dis-
abled (GPSMODE0 = 0).

In the case that GPSMODE pins with internal pull-up or pull-down resistors are connected to
GND/VDD18, additional current is drawn over these resistors. Especially GPSMODE3 can
impact the back-up current.

3.3.1

Enable GPSMODE Pin Configuration

If the GPSMODE configuration is enabled (GPSMODE0 = 1) and the other GPSMODE pins are
not connected externally, the reset default values of the internal pull-down and pull-up resistors
will be used.

Table 3-3.

GPSMODE Functions

Pin

Function

GPSMODE0 (P1)

Enable configuration with GPSMODE pins

GPSMODE1 (P9)

This pin (EXTINT0) is used for FixNOW

™

functionality and not used for GPSMODE

configuration.

GPSMODE2 (P12)

GPS sensitivity settings

GPSMODE3 (P13)

GPSMODE4 (P14)

This pin (NAADET1) is used as active antenna supervisor input and not used for
GPSMODE configuration. This is the default selection if GPSMODE configuration is
disabled.

GPSMODE5 (P17)

Serial I/O configuration

GPSMODE6 (P19)

GPSMODE7 (P23)

USB power mode

GPSMODE8 (P24)

General I/O configuration

GPSMODE9 (P25)

This pin (NAADET0) is used as an active Antenna Supervisor input and not used for
GPSMODE configuration

GPSMODE10 (P26)

General I/O configuration

GPSMODE11 (P27)

GPSMODE12 (P29) Serial I/O configuration

Table 3-4.

Enable Configuration With GPSMODE Pins

GPSMODE0

(Reset = PD) Description

(1)

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

Use settings as specified with GPSMODE[2, 3, 5 to 8, 10 to 12]

Note:

1. Leave open