ATR0621 Datasheet, PDF (11/20 Pages) ATMEL Corporation – GPS Baseband Processor

ATR0621 [Preliminary]
3.3.3
Serial I/O Configuration
The ATR0621 features a two-stage I/O message and protocol selection procedure for the two
available serial ports. At the first stage, a certain protocol can be enabled or disabled for a
given USART port. Selectable protocols are RTCM, NMEA and UBX. At the second stage,
messages can be enabled or disabled for each enabled protocol on each port. In all configura-
tions discussed below, all protocols are enabled on all ports. But output messages are
enabled in a way that ports appear to communicate at only one protocol. However, each port
will accept any input message in any of the three implemented protocols.
Table 3-6. Serial I/O Configuration
USART1
USART2
GPSMODE12 GPSMODE6 GPSMODE5 (Output Protocol/ (Output Protocol/
(Reset = PU) (Reset = PU) (Reset = PD) Baud Rate (kBaud)) Baud Rate (kBaud)) Messages Information Messages
0
0
0
UBX/57.6
NMEA/19.2
High
User, Notice, Warning, Error
0
0
1
UBX/38.4
NMEA/9.6
Medium User, Notice, Warning, Error
0
1
0
UBX/19.2
NMEA/4.8
Low
User, Notice, Warning, Error
0
1
1
–/Auto
–/Auto
Off
None
1
0
0
NMEA/19.2
UBX/57.6
High
User, Notice, Warning, Error
1
0
1
NMEA/4.8
UBX/19.2
Low
User, Notice, Warning, Error
1
1
0
NMEA/9.6
UBX/38.4
Medium User, Notice, Warning, Error
1
1
1
UBX/115.2
NMEA/19.2
Debug
All
Both USART ports accept input messages in all three supported protocols (NMEA, RTCM and
UBX) at the configured baud rate. Input messages of all three protocols can be arbitrarily
mixed. Response to a query input message will always use the same protocol as the query
input message.
In Auto Mode, no output message is sent out by default, but all input messages are accepted
at any supported baud rate. Response to query input commands will be given the same proto-
col and baud rate as it was used for the query command. Using the respective configuration
commands, periodic output messages can be enabled.
The following message settings are used in Table 3-6:
Table 3-7.
NMEA Port
UBX Port
Supported Messages at Setting Low
Standard GGA, RMC
NAV
SOL, SVINFO
Table 3-8.
NMEA Port
UBX Port
Supported Messages at Setting Medium
Standard GGA, RMC, GSA, GSV, GLL, VTG, ZDA
NAV
SOL, SVINFO, POSECEF, POSLLH, STATUS, DOP, VELECEF,
VELNED, TIMEGPS, TIMEUTC, CLOCK
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4890AS–GPS–09/05