Hi everybody. I am hoping somebody else has had this problem and has since corrected it. I flashed the Dragonboard with the latest release of debian (#110 image) and then proceeded to install the GPIO access libraries. I had first installed the Libsoc, MRAA, and UPM from the latest git sources, but there have been some changes in the libraries that have caused some inconsistencies with the examples. To simplify things, I reflashed the board with the #110 image and then installed Libsoc, MRAA, and UPM from the repos (i…e using apt-get). Since there is no 96BoardsGPIO library in the debian repo, I installed that from the GitHub master branch. After following the install guide, I get the following output when performing a logon to the DragonBoard:
-bash: export:
[board]’: not a valid identifier
-bash: export: [GPIO]': not a valid identifier -bash: export:
GPIO-A=36’: not a valid identifier
-bash: export: GPIO-B=12': not a valid identifier -bash: export:
GPIO-C=13’: not a valid identifier
-bash: export: GPIO-D=69': not a valid identifier -bash: export:
GPIO-E=115’: not a valid identifier
-bash: export: GPIO-F=4': not a valid identifier -bash: export:
GPIO-G=24’: not a valid identifier
-bash: export: GPIO-H=25': not a valid identifier -bash: export:
GPIO-I=35’: not a valid identifier
-bash: export: GPIO-J=34': not a valid identifier -bash: export:
GPIO-K=28’: not a valid identifier
-bash: export: GPIO-L=33': not a valid identifier -bash: export:
GPIO-23=36’: not a valid identifier
-bash: export: GPIO-24=12': not a valid identifier -bash: export:
GPIO-25=13’: not a valid identifier
-bash: export: GPIO-26=69': not a valid identifier -bash: export:
GPIO-27=115’: not a valid identifier
-bash: export: GPIO-28=4': not a valid identifier -bash: export:
GPIO-29=24’: not a valid identifier
-bash: export: GPIO-30=25': not a valid identifier -bash: export:
GPIO-31=35’: not a valid identifier
-bash: export: GPIO-32=34': not a valid identifier -bash: export:
GPIO-33=28’: not a valid identifier
-bash: export: `GPIO-34=33’: not a valid identifier
As a result, the GPIO shell commands do not work when following the “through the shell” example. When performing a command line … echo $GPIO_A > export … the system responds with “bash: echo: write error: Invalid argument”. This happens when using $GPIO_A or $GPIO-A. It also happens when using the number rather than the letter.
However, the programmatic examples work just fine. I created a small demo similar Blink.c using a switch and LED and was able to access GPIO-A and GPIO-C using the letter designations… so it works. I am just not sure how to get rid if the above error messages. Any advice?