minicom from raspberry pi

[Osman Gutiérrez]

From vehiclepi's raspberry pi I am trying to connecting to ttyAMA0 with "minicom" command

$ minicom -o -b 500000 -D /dev/ttyAMA0

Welcome to minicom 2.6.1

OPTIONS: I18n 

Compiled on Apr 28 2012, 19:24:31.

Port /dev/ttyAMA0

Press CTRL-A Z for help on special keys

+GPS=$GPGGA,,,,,,0,00,,,M,0.0,M,,0000*48

+GPS=$GPGSA,A,1,,,,,,,,,,,,,,,*1E

+GPS=$GPGSV,3,1,12,01,00,000,,02,00,000,,03,00,000,,04,00,000,*7C

+GPS=$GPGSV,3,2,12,05,00,000,,06,00,000,,07,00,000,,08,00,000,*77

+GPS=$GPGSV,3,3,12,09,00,000,,10,00,000,,11,00,000,,12,00,000,*71

+GPS=$GPRMC,,V,,,,,,,,,,N*53

+GPS=$GPGGA,,,,,,0,00,,,M,0.0,M,,0000*48

+GPS=$GPGSA,A,1,,,,,,,,,,,,,,,*1E

I am receiving only +GPS and +TERM output, Is that nomal? What about +GSM?

Regards

[Kalin Nakov]

By default the GSM is switched off. You need to enable it first.

Step 1:

Turn on the GSM's power supply

AT+CPU=GSM:ON

... wait for a couple of seconds

Step 2:

Switch on the GSM (activate it)

AT+CPU=GSM:SWITCH

... wait for a couple of seconds

Step 3:

Send a command to the GSM

AT+GSM=ATZ

When power saving is needed, you can switch off the GPS by

AT+CPU=GPS:SWITCH

Take a look at the VehiclePiDemoTCPConnectAsyncTask.java demo code to see how the GSM module is enabled and how to establish a bidirectional TCP connection. Note the timeouts when booting the GSM module.

Note: You have to provide 12V power supply, at least 1.5A on the mains plug to be able to use the GSM and ECU connectivity.

[Osman Gutiérrez]

Hello Kalin,

Thanks for the hint. I changed VehiclePiDemoTCPConnectAsyncTask.java for launch it on Raspberry using /dev/ttyAMA0, I am getting this error.

>>> AT+CPU=GSM:SWITCH

An error has occurred: ?AT+CPU=GSM:SWITCH

Accelerometer horizontal acceleration: -0.232 m/s2

>>> AT+CPU=GSM:OFF

>>> AT+CPU=GSM:ON

>>> AT+CPU=GSM:SWITCH

>>> AT+GSM=ATZ

The same if I send these commands using minicom.

Note: I am using the raspberrypi with AC Power Supply.

Regars

[Kalin Nakov]

Take a look at this topic: https://groups.google.com/forum/embed/?place=forum/viacont&showsearch=true&showpopout=true&parenturl=https%3A%2F%2Fwww.viacont.com%2Fsupport.html#!topic/viacont/EByh8uxhseo

The demo example did not reflect the work around for this Raspbian kernel bug. We will update the example in the next SDK release. In the meanwhile, you need to send a dummy command as the first command ever after opening the serial port. For example, send a plain vanilla empty string with IVehicleDriver.send("") or when in the minicom console, press Enter after opening the port. This will scoop out the garbage character and after that each command will work.