sirf3.c File Reference

dissect SiRF binary input message More...

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "gps-parser.h"
#include "sirf3.h"

Functions
void	sirf_static_nav (usart_control_t *usart)
	Static Navigation.
void	sirf_gps_off (usart_control_t *usart)
	power off GPS module
gps_line_status_t	sirf_recvd (gps_parser_t *parser, usart_rxdata_t c)
	give one character to SiRF parser
gps_proto_parser_t *	new_sirf_parser (gps_parser_t *parser)
void	free_sirf_parser (gps_parser_t *parser)
Variables
const gps_proto_functions_t	gps_proto_sirf
const gps_proto_functions_t gps_proto_sirf	PROGMEM

---

Detailed Description

dissect SiRF binary input message

reference: http://gpsd.googlecode.com/files/SiRF-SiRF-v2_4.pdf

Interesting SiRF binary input messages:

• Measure Navigation Data Out (SIRFo_NAV) (41 Bytes) 1 Hz
  • (4S) X-Position in m
  • (4S) Y-Position in m
  • (4S) Z-Position in m
  • (2S) X-Velocity*8 in $m/sec$
  • (2S) Y-Velocity*8 in $m/sec$
  • (2S) Z-Velocity*8 in $m/sec$
  • (1) Mode1 (bitmap)
    • bit0/1/2 PMODE
      • 0 no navigation solution
      • 1 1-SV solution (Kalman filter)
      • 2 2-SV solution (Kalman filter)
      • 3 3-SV solution (Kalman filter)
      • 4 4 or more SV solution (Kalman filter)
      • 5 2D point solution (least squares)
      • 6 3D point solution (least squares)
      • 7 Dead Reckoning
    • bit3 TPMODE Trickle Power Mode
      • 0 full power position
      • 1 TricklePower position
    • bit4/5 ALTMODE Altitude mode
      • 0 no altitude hold
      • 1 altitude held from filter
    • bit6 DOPMask DOP mask status
      • 0 DOP mask not exceeded
      • 1 DOP mask is exceeded
    • bit7 DGPS DGPS status
      • 0 no differential corrections used
      • 1 differential corrections
  • (1U) HDOP/5
  • (1) Mode2 (bitmap)
    • bit0
    • bit1 if set, solution is validated (>=5 SVs)
    • bit4 if set, velocity is invalid
    • bit5 altitude hold mode: if set disabled
  • (2U) GPS Week
  • (4U) GPS Time of Week*100 in s
  • (1U) Satellites in Fix
  • (12U) Channel x PRN

---

Function Documentation

void sirf_gps_off

(

usart_control_t *

usart

)

power off GPS module

poll Software Version

{
  static const uint8_t msg [] = {SIRFi_SOFT_CTRL, SIRFi_SOFT_OFF};
  sirf_send_msg (usart, msg, sizeof (msg));
  usart_flush (usart);
#if 0
  /* the GPS module is of no use to us until a power-cycle,
   * so cut power to USART */
  usart_disable (usart);
  usart_poweroff (usart);
#endif
}

---

Variable Documentation

const gps_proto_functions_t gps_proto_sirf PROGMEM

Initial value:

 {
  .newparser = new_sirf_parser,
  .freeparser = free_sirf_parser,
  .recvd = sirf_recvd,
  .switchproto = sirf_switch,
  .proto = GPSPROTO_SiRF,
  .baudrate_max = 115200,
}