Valueerror invalid gpio pin specified

rahulpelluri · March 23, 2018, 6:07pm

i have tried to run the command
p=mraa.Gpio(24)
the error that is displayed says
ValueError: Invalid GPIO pin specified.

Please tell me what I must do. I am a complete newbie to embedded systems.

Mani · March 23, 2018, 7:33pm

Hello,

Please provide the following info for nailing down the issue:

Linaro debian release version
Mraa version

If you are using latest debian and latest Mraa, then there might be some issues with Chardev support in gpio for Mraa. I will submit a patch in next few days for fixing that.

Thanks,
Mani

rahulpelluri · March 24, 2018, 4:31am

Thank you for the quick reply.
My Debian version is 9.4 and the mraa version is 1.9.0
So I guess both are latest versions. Could you please tell me when and form where must I install the new mraa version.
Thanks
Rahul

rahulpelluri · March 28, 2018, 5:38am

HI Mani,
Has the update been made?

Mani · March 28, 2018, 4:00pm

Hi @rahulpelluri,

Sorry for the delay. Can you please post the log from mraa?

It can be obtained by the following command:

$ tail -n 100 /var/log/syslog

-Mani

rahulpelluri · March 30, 2018, 2:32pm

Mar 30 14:02:02 linaro-alip libmraa[2373]: libmraa version v1.9.0 initialised by user ‘linaro’ with EUID 1000
Mar 30 14:02:02 linaro-alip libmraa[2373]: imraa: Failed to open lock file
Mar 30 14:02:02 linaro-alip libmraa[2373]: libmraa initialised for platform ‘DB410C’ of type 9

rahulpelluri · March 30, 2018, 2:34pm

Mar 30 14:02:02 linaro-alip libmraa[2373]: libmraa version v1.9.0 initialised by user ‘linaro’ with EUID 1000

Mar 30 14:02:02 linaro-alip libmraa[2373]: imraa: Failed to open lock file

Mar 30 14:02:02 linaro-alip libmraa[2373]: libmraa initialised for platform ‘DB410C’ of type 9

Mani · March 30, 2018, 3:52pm

Looks like there is no issue with Chardev implementation. Can you please try to build and install mraa from source? Instructions can be found in the below guide:

github.com

96boards/documentation/blob/master/consumer/guides/mraa/install.md

---
title: Guides
permalink: /documentation/consumer/guides/mraa/install.md.html
redirect_from: /documentation/ConsumerEdition/guides/mraa/install.md.html
---

# Installation guide for MRAA library on 96Boards CE

Following instructions provides information about installing the MRAA library as a package and building from source.

## Update 96Boards system

The image on your board might be out of date. This is possible even when using the stock image (the operating system your board was shipped with), or a newly flashed version from the 96Boards.org website.

A few useful commands will help us make sure everything on the board is current:

- **apt-get update**: Downloads package lists from online repositories and "updates" them to get information on the newest versions of packages and their dependencies.
- **apt-get upgrade**: Fetches and installs newest package versions which currently exist on the system. APT must know about these new versions by way of 'apt-get update'
- **apt-get dist-upgrade**: In addition to performing the function of upgrade, this option also intelligently handles changing dependencies with new versions of packages

This file has been truncated. show original

Then try to run some sample examples:

Thanks,
Mani

rahulpelluri · April 28, 2018, 8:18am

Hi Mani,
I have tried what you have asked me to. It didnt work. I have even reinstalled the operating system and have tried again. I am not even able to access the GPIO pins from the command line. What could be the issue. There was a pre installed mraa package in the OS and it also did not work on the python commands.

Peeyush_Tekriwal · August 28, 2019, 8:43am

Did the issue get solved? I am also getting the same error as
module ‘mraa’ has no attribute ‘Gpio’

Mani · August 28, 2019, 10:44am

@Peeyush_Tekriwal Please try to build and install mraa from source as mentioned in the guide

Peeyush_Tekriwal · August 28, 2019, 11:19am

I have done that and it is built. Why is it showing the error now? My kernel version is 4.14.0