I2C GPIO Support

[Luuii]

Is there a develop library i2c built in the new Coder GPIO Module ?

[derhexer13]

We need i2c too. Is there any way to access i2c via the gpio module? Our school project is a web based weather station... raspberry pi with coder with i2c... the solution!

[herschar]

Is it useful to install i2c as described below? http://www.instructables.com/id/Raspberry-Pi-I2C-Python/

If yes -> how to login? (need login name and password of coder)

[jmstriegel]

I'll add the pi-spi and i2c node modules to the coder package. I haven't done a lot of development or testing with these yet, so if you are hacking with this and have experience here, please let me know.

[Luuii]

I have installed the I2C modules from npm and it works very well in coder v0.5. There is no difficult to install de module if your follow the instructions from https://www.npmjs.org/package/rasp2c. I did via ssh. The module can detect i2c addresses and behave like a I2C Master.

[derhexer13]

I've installed the the i2c and bmp085 packages and i can detect my i2c module by using the console and i2cdetect command. That's all i can do. If i attempt to use BMP05 in my JS in coder i get an error.

//This code results in an error... var BMP085 = require('sensor_bmp085'); var sense = new BMP085(); // <--- ERROR here : Uncaught TypeError: object is not a function

$(document).ready( function() {

//This code will run after your page loads

sense.init(function(err, val) {
  if (!err) {
    sense.getTemperature(function(error, val) {
      if (!error) {
        console.log(val + ' °C');
        sense.getPressure(function(error, val) {
          if (!error) {
            console.log(val + ' °C');
          }
        });
      }
    });
  }    
});

});

[jmstriegel]

Got a test working with pi_spi to read data from the MCP8003 analog to digital converter. https://github.com/googlecreativelab/coder/tree/master/coder-apps/tests/spi_test

I'll order a BMP085 sensor to build a test for I2C.

[jmstriegel]

I've uploaded a fresh new image that contains the i2c and pi-spi modules. Get it here: http://googlecreativelab.github.io/coder/#download

BTW, here's the docs on these: https://github.com/natevw/pi-spi https://github.com/kelly/node-i2c

[Luuii]

Hi Jason, I got a test good working with the I2C Devices MCP23017 Port Expander

Passing trough to an another subject, I I would like to know how you do a Coder image with the new requirements. In order to keep simplicity, I would like to do a versión with my own and custom modules, default web apps and custom properties. If I have this, I could only share the image and copy to anyone.

[jmstriegel]

@Luuii I basically do this:

• develop on a device to get it where I want. commit all my changes.
• start with a clean image
• bring in and apply all the updates I've made from git
• set the device up with defaults that i want
• clean up logs and user files with /root/clean_device.sh
• shutdown, eject sd, and use the dd utlity on a mac to make an image of the disk.

On the mac you put the disk in, then unmount it with:

sudo diskutil unmount /dev/disk2s1

/dev/disk2 on my machine is where my sdcard pops up. You'll need to adjust if this is different. Then you image it with:

dd bs=1m if=/dev/rdisk2 of=raspi.img count=2900

That's copying 2900 1-MB blocks, which is enough to get the partitions plus a little to spare. If you change the partition table, you'll need to do the math and adjust as necessary.

[Luuii]

Thank you Jason, in the next time I will try to do your specifications and I will maintain contact.