How to switch to sirf from nmea & push to fix mode

Hi all, I would like to know how to make the gps receiver run in the low power.

Below are the msg that i have send to the gps module to trigger it. BUT NOTHING HAPPENNED btw, my gps receiver are running in nmea after power on. 'it's so confusing. i couldnt a good reference website from internet.

1)switch to sirf from nmea
$PSRF100,0,9600,8,1,0*0C


2)active push to fix on
A0A2000997000100C8000000C80228B0B3

3)set max. sleeptime and sattellite search time.
A0A20019A70000753000000E10000000000000000000000000 00000000016AB0B3


I have only used these 3 messeges to turn on my push to fix mode. pls correct me. I know it's not enough. I need a complete messeges I should send to the gps module work in low power. and when should i set coldstart/warmstart/hotstart?

Thanks.
p/s: i hope my questions r not confusing u alot. bcos I already very confuse.

sorry.

~qbee

Do you need the messages or just a way to change your unit? If it is the latter, you can just get a program caller sirfinfo. :google:

I need to write a c program to trigger my gps module into low power mode.

Q1, Could somebody check for me is this a complete steps to make the push to fix work?

1) I'll receive a fix from the gps modele in nmea mode.

2) convert those data into into ecef x,y,z

3) setserialport MID100 to switch to sirf from nmea.

4) i reckon im in sirf more now. put item (2) ecef x,y,z into initialize data source (msg ID 128)

5) set development data on MID105

6) active push to fix with command set trickle power parameters (ID 151)

7) set max. sleeptime and sattellite search time with command low power acquisition parameters (ID167)

Q2, if I want to receive the next fix, I need to switch to nmea again with command 100? when is the right time to switch back to nmea.

Q3, in command 167, what is the purpose of the sattelite search time?

Q4, btw, where can we get a complele guideline for sirf bside sirf.com.

Q5, when we need Cold/warm/hot start?

Thanks :nw: