Help on LBS

[tulipneo]

HI List,
I Need a bit help on the following.I just got soem cose from forum to test the LBS functionality from Google MAP.The author of the code has hard coded the following values

cellId = 41508 lac = 18007 mnc = 76 mcc = 404.
Whe i use this to ping google i get good results for Latitude and longitude with following code.If i use mcc, mnc, lac, cellId) = location.gsm_location()
I get CID = 118040699 LAC = 18007 MCC = 404 MNC = 76 .If i use these values to ping google than i dont get any value from google map.Can any one suggest on this.any pointer would of great help to me.

Br
Tulip

import urllib2
import location
import sysinfo

url = 'http://www.google.com/glm/mmap'
string1 = '000E00000000000000000000000000001B0000000000000000000000030000'
string2 = 'FFFFFFFF00000000'

def make_string(value):
    hex_s = hex(value)[2:]
    return hex_s.zfill(8)

def fetch_latlon(bytestring):
    global url
    user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'
    headers = { 'User-Agent' : user_agent }
    req = urllib2.Request(url, bytestring, headers)    
    resp = urllib2.urlopen(req)    
    response = resp.read().encode('hex')    
    return response

def convert_bytestring(response):
    lathex_s = response[14:22]
    lonhex_s = response[22:30]
    lat = float(int(lathex_s,16))/1000000
    lon = float(int(lonhex_s,16))/1000000
    return (lat,lon)

def main(cid,lac,mnc,mcc):
    global string1, string2
    string = string1+make_string(cid)+make_string(lac)+make_string(mnc)+make_string(mcc)+string2
    b_string = string.decode('hex')
    bytes = fetch_latlon(b_string)
    (a,b) = convert_bytestring(bytes)
    print a
    print b


cellId = 41508
lac = 18007
mnc = 76
mcc = 404
#(mcc, mnc, lac, cellId) = location.gsm_location()
main(cellId,lac,mnc,mcc)

[gaba88]

hello

First thing you should do is debug your srcipt and check wheather you are getting correct cell id and other other parameters, then we can move ahaead.

Regards

[tulipneo]

Hi Gargi,
I knew atleast u r going to reply me like u help others every time.
Well i get values as bellow:

cellId = 118041508 lac = 18007 mnc = 76 mcc = 404
First thing how do i make sure/Debug that these are correct values.
Second thing my application gives me lat and long when i use the parameter given by author who posted the code.
ie.
CID = 20465 LAC = 495 MNC = 3 MCC = 262

If i analyse both the data i get surprised as author's cellid value is only 5 octets.

Pls suggest on this.

Br
Tulip

[tulipneo]

Hi Gargi,
Further more from GSP spec GSM 11.14 version 5.2.0

I get following interpretaion..

from GSM specs i could get to know that

Byte(s) Description Length
1 Location Information 1
2 Length (X) of bytes following 1
3-5 Mobile Country & Network Codes (MCC & MNC) 3
6-7 Location Area Code (LAC) 2
8-9 Cell Identity Value (Cell ID) 2

So i wonder how do i get such a big cell id value.

So if u look above the total octet is 9 octet.is it the case that the cellid i get 118041508(9 octets) is this octet.

Br
Tulip

[gaba88]

Hi Gargi,
I knew atleast u r going to reply me like u help others every time.
Well i get values as bellow:

cellId = 118041508 lac = 18007 mnc = 76 mcc = 404
First thing how do i make sure/Debug that these are correct values.
Second thing my application gives me lat and long when i use the parameter given by author who posted the code.
ie.
CID = 20465 LAC = 495 MNC = 3 MCC = 262

If i analyse both the data i get surprised as author's cellid value is only 5 octets.

Pls suggest on this.

Br
Tulip

hello tulip

that cellid value sound fishy can you edit your first post and add the code tags there so that i can have a good look at the code.

Enjoy Pythoning

[tulipneo]

Sorry Gargi I did not understand you.I mean what exactly u mean by code tag.
My first post alreday contains the code.

Br
Tulip

[gaba88]

i mean just edit your post and add the code tags, code tags are with # symbol on your forum nokia thread editor.

Hope you got that.

[tulipneo]

Hi Gargi,
Code tagged in first post.

Br
Tulip

[gaba88]

hello tulip

indeed a great script just checked with N97 PyS60 1.9.7 and that returns the exact cellid of my office.

so now i guess the problem may be with your network operator can you check that with some other operator??

Regards,

[tulipneo]

I will do so right away and ping u back.Just added you to Gtalk

Br
Tulip

[tulipneo]

In The code the bellow line was commented
(mcc, mnc, lac, cellId) = location.gsm_location()
did u uncomment and test it.i used some hard coded value and it worked but did not work with location.gsm_location() values

Br
Tulip