The GM862 is a module that integrates a GSM modem, a GPS receiver and a Python interpreter.
The module features a file system. It doesn't support directories but it does support any files ( not just Python scripts) as long as the file names are no longer than 16 characters.
Most of the tools available for the GM862 are for Windows. The archive below includes a command-line tool called
gm862. The tool requires that a serial port be present and connected to the GM862. Edit
./gm862 if your serial port is not at
The script has sub-commands:
||Shows a list of the files on the module|
||Uploads all the files given as arguments to the module|
||Removes all files given as arguments from the module|
||Shows which script will be booted when the module is started|
||Sets the active script that the module runs when it boots|
||Runs the active script immediately without the need for a power cycle|
$ ./gm862 help boot boots help list rm run upload $ ./gm862 list #LSCRIPT: "Test.py",1981 #LSCRIPT: "NMEA.pyo",1364 $ ./gm862 upload Main.py $ ./gm862 list #LSCRIPT: "Test.py",1981 #LSCRIPT: "NMEA.pyo",1364 #LSCRIPT: "Main.py",3226 $ ./gm862 rm Test.py $ ./gm862 list #LSCRIPT: "NMEA.pyo",1364 #LSCRIPT: "Main.py",3226 $ ./gm862 boots #ESCRIPT: "Test.py" $ ./gm862 boot Main.py $ ./gm862 boots #ESCRIPT: "Main.py" $ ./gm862 run
There are some other files in the archive:
HelloWorld.py Modem.py debug.py traceback.py
Modem.py wraps some AT commands and provides a nice API to:
traceback.py is a cut-down copy of the file of the same name from Python 1.5.2. The
traceback Python module is not included on the device and is required by
debug.py provides a tidy way of sending nicely formatted debugging output but it also provides much needed support for catching and reporting exceptions on the module. Use it like this:
False, True = 0, 1 import SER import MOD SER.set_speed('4800') SER.send("System initialization in progress..\r\n") from debug import * db("Debugging support is now available.") try: db("Initializing modem..") from Modem import Modem modem = Modem() # Wait up to 15 seconds to get registered on the network: when_began_waiting = MOD.secCounter() while MOD.secCounter() < when_began_waiting + 15: if modem.is_registered(): break MOD.sleep( 1) db(" registered on network: %s"% "Ny"[modem.is_registered()]) db(" complete.") should_run = True while should_run: MOD.sleep( 10) except Exception, e: report_error( e)
This is a considerable improvement over having the software crash with an exception and having no error output whatsoever.
screencan be used to interact with the module. Invoke:
screen /dev/ttyUSB0 9600
DTR HIposition to automatically run the active script upon power up.
.pyfile for the module and it will be compiled on the module when first imported ( although this can take a few seconds). It will not be re-compiled, which is good for reducing boot time in production but the
.pyofiles must be removed when an updated
.pyfile is uploaded