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Tips and questions relating to the GPS modules from SFE
By juffyvega12590
#121322
I have GM862 -GPS evaluation kit. I bought it here in sparkfun a month ago.
http://www.sparkfun.com/products/478

At first there is no problem in uploading and executing python scripts in the module.
But after a couple of times writing and executing python scripts in the module, it then became unstable.

When DTR is set to high (programming mode) I have no problem in executing AT commands in the module, but after uploading a script and setting the DTR to low (Execution mode) and then rebooting the device, there is no reaction coming from the module.

I tried rebooting the device for a couple of times but it seems no reaction.

I am using Rsterm in uploading Python scripts into the module. And here is the code i made, it is not yet finish but it compiles and works fine.


##### Config #####

sms_password = 'jubela'

##### Constants #####

TRUE = 1
FALSE = 0
LOOP = 1
SPEEDLIMIT = 30

##### Modules #####

#Use serial
import SER

#Use build in module
import MOD

#Use AT command interface
import MDM

#Use GPS
import GPS

###### General Functions ######

#Debug message
def debugmsg(msgtext):
msgtext = msgtext.replace('\r', '\\r')
msgtext = msgtext.replace('\n', '\\n')
print msgtext
SER.send(msgtext + '\r\n')
#f = open('log.txt','ab')
#f.write(msgtext + '\n')
#f.close()

#GPS status
def gps_status(gpspos):
debugmsg('Retrieving GPS status')

gpspos_parts = gpspos.split(',')

if ( (gpspos_parts[5] == '2') or (gpspos_parts[5] == '3') ): #2D or 3D fix
#debugmsg('GPS fix "' + gpspos_parts[5] + '" ie valid');
status = TRUE
else:
#debugmsg('GPS fix "' + gpspos_parts[5] + '" ie not valid');
status = FALSE

return status

###### SMS Library Functions ######

#Setup SMS
def sms_setup():

debugmsg('Setting up SMS')

MDM.send('AT+CMGF=1\r', 0)
res = MDM.receive(50)#5 sec
MOD.sleep(1)#wait 0.1sec

debugmsg('SMS setup: ' + res)

def testspeed(gpspos):

#debugmsg('Test if speed is over limit')

gpsdataparts = gpspos.split(',')
currentspeed = gpsdataparts[7]
debugmsg('Time is ' + gpsdataparts[0] + ' UTC time')
debugmsg('latitude is ' + gpsdataparts[1])
debugmsg('longtitude is ' + gpsdataparts[2])
debugmsg('heading is ' + gpsdataparts[6])
debugmsg('Speed is ' + gpsdataparts[7] + ' km/hr')
debugmsg('date is ' + gpsdataparts[9])

if (gps_status(gpspos) == TRUE):
debugmsg('Has GPS Fix')
if (float(gpsdataparts[7]) < 60.0):
debugmsg('Speed UNDER the speed limit')

else:
debugmsg('Has NO GPS Fix to be tested for overspeeding')

##################################################################################

###### Init ######

SER.set_speed('115200','8N1')
SER.send('\r\n--------------------\r\n\r\n')

debugmsg('Running...');

#Set verbose error reporting
MDM.send('AT+CMEE=2\r', 0)
MDM.receive(50)#5 sec
MOD.sleep(1)#wait 0.1sec

#Setup SMS
sms_setup()

#Main loop
while (LOOP==1):

debugmsg('Entering loop')

#Retrieve current position
gpspos = GPS.getActualPosition()

debugmsg('Position: %s' % gpspos)

#Retrieve GPS fix status
gps_statusnow = gps_status(gpspos)

#Save last valid position
#If position fix valid, or none recorded already, use last retrieved
if ( (gps_statusnow == TRUE) or (gps_statusnow == FALSE) ):
testspeed(gpspos)

debugmsg('Powersave for 10 seconds')

#Powersave for 10 seconds
MOD.powerSaving(10)




I don't know why this is happening. It cost me a lot in buying this device and now turns out like this.

Is there any solution in making the module stable again?
Do I need to upgrade my firmware from .400 to 403?
Or maybe the problem is on my script?
By mzed
#149525
Hello,

How did you solve the problem occuring on GM862-GPS with sparkfun EVK ?
Even a simple script doesn't seem to be executed by the module.

import SER
a=SER.send("hello world")

The module hangs until I switch it off. No commands are accepted.There are some symbols displayed on the terminal screen.

Any idea or clue please ? It would be very helpfull.

Thanks
By belkacem
#160545
I'm having some trouble to update my GM862-GPS Firmware :

after few moment the xfp tool shows the error message :

Error : FlashsendStream - Error rx (0x000061B2 -0x000161B1), Code:0 (Code: -9)

please can you help me to figure this out.