Manual

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