6 Replies Latest reply on Apr 16, 2015 8:43 AM by Intel_Peter

    Edison I2C Problem With Grove RGB LCD...

    DangerousTim

      I'm using an Edison on a Arduino breakout board. Recently i reflashed the board because of a corrupted image, and now all seems ok during boot. The version I flashed was 16. I uploaded the blink sketch: It worked. The grove lcd hello world sketch worked too. Then i upgraded the image to version 120. Then again after setup and all i uploaded the lcd test sketch. I could see the lcd was receiving power, but no text was displayed, nor did the backlight work. I tried connecting the lcd directly to A4/A5 AND SDA/SCL, in all possible configurations, but nothing worked.

       

      It seems something happened after the upgrade. Should I be installing some package or something? I have already created an unofficial opkg repository and run an opkg update. I think the I2C isnt working for some unknown reason... Please HELP!!!

        • 1. Re: Edison I2C Problem With Grove RGB LCD...
          Intel_Peter

          Hi DangerousTim,

           

          How are you programming the LCD?  Are you using the Arduino IDE? Or are you using MRAA? If so, have you updated it to the latest version? Could you share your code?

           

          Peter.

           

          Edit: Is this your LCD?

          • 2. Re: Edison I2C Problem With Grove RGB LCD...
            DangerousTim

            Yes, that's my LCD.

            I tried both python and Arduino. Both worked before I reflashed and upgraded the board.

            • 3. Re: Edison I2C Problem With Grove RGB LCD...
              Intel_Peter

              Can you share your code? Both the one made in Python and the one for the Arduio IDE.

              Are you using the latest version of MRAA?

               

              Peter.

              • 4. Re: Edison I2C Problem With Grove RGB LCD...
                DangerousTim

                uhhh... i can't find the python code, so here's the Arduino code...

                 

                #include <LiquidCrystal.h>

                 

                 

                // initialize the library with the numbers of the interface pins

                LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

                 

                 

                void setup() {

                  // set up the LCD's number of columns and rows:

                  lcd.begin(16, 2);

                  // Print a message to the LCD.

                  lcd.print("hello, world!");

                }

                 

                 

                void loop() {

                  // set the cursor to column 0, line 1

                  // (note: line 1 is the second row, since counting begins with 0):

                  lcd.setCursor(0, 1);

                  // print the number of seconds since reset:

                  lcd.print(millis()/1000);

                }

                • 5. Re: Edison I2C Problem With Grove RGB LCD...
                  DangerousTim

                  And well i have another proble... why do i get so little space?

                  root@edison:~# df -h

                  Filesystem                Size      Used Available Use% Mounted on

                  /dev/root               463.9M    393.9M     34.2M  92% /

                  devtmpfs                479.9M         0    479.9M   0% /dev

                  tmpfs                   480.2M         0    480.2M   0% /dev/shm

                  tmpfs                   480.2M    504.0K    479.7M   0% /run

                  tmpfs                   480.2M         0    480.2M   0% /sys/fs/cgroup

                  systemd-1                 5.7M      5.3M    462.0K  92% /boot

                  tmpfs                   480.2M      1.7M    478.5M   0% /tmp

                  systemd-1                 2.2G      3.7M      2.2G   0% /home

                  tmpfs                   480.2M         0    480.2M   0% /var/volatile

                  /dev/mmcblk0p5         1003.0K     19.0K    913.0K   2% /factory

                  /dev/mmcblk0p10           2.2G      3.7M      2.2G   0% /home

                  /dev/mmcblk0p7            5.7M      5.3M    462.0K  92% /boot

                   

                  only 34mB in /dev/root/ ?! Why cant i use /dev/mmcblk0p10  instead? I've cleared the journal logs too...

                  • 6. Re: Edison I2C Problem With Grove RGB LCD...
                    Intel_Peter

                    Sorry for the delay in my response. Regarding your last question about why do you have so little free space on your Edison, it might be because of several reasons, you could have a lot of packages installed on your Edison that fill up completely the Edison's memory; other explanation for this situation could be that /var/log/journal takes a lot of space, if this is the case, you can free up some space by doing the following:

                     

                    rm -rf /var/log/journal/*
                    umount /etc/machine-id
                    systemd-machine-id-setup
                    rm -rf /var/log/journal/*
                    reboot
                    

                     

                    Either way, you could take a look at Increasing the Root Partition Size, to learn how to increase the partition size of rootfs. However, as you can see in Re: Root size limit... Release 2 has a rootfs partition 1.4GB but Edison needs to be flashed with the flashall method in order to repartition its internal storage.

                     

                    Regarding your original question, could you attach the library that you are using?

                     

                    Peter.