wraggster
September 15th, 2012, 23:43
http://hackadaycom.files.wordpress.com/2012/09/adc.jpeg
Much to the chagrin of hardware tinkerers, the Raspberry Pi doesn’t have analog inputs on its GPIO pins. Sure, you can blink a LED with just a few console commands, but reading sensors with a bone-stock Raspi requires a little additional hardware. [Brian Dorey] just released a board that allows for 8 analog inputs (http://www.briandorey.com/post/ADC-Pi-Raspberry-Pi-I2C-Analog-to-Digital-Converter-boards-available-to-buy-online.aspx) on the Raspberry Pi with a 16-bit resolution that is much higher than any Arduino-based build.
[Brian]‘s build is based on an earlier, similar iteration (http://hackaday.com/2012/07/25/raspberry-pi-keeps-tabs-on-your-solar-power-setup/) of a Raspi analog board we saw last July. Like the previous version, the new professionally made PCBs use a pair of Microchip MCP3428 analog to digital converter. These ADCs are able to sample four channels at a resolution of 16 bits; a vast improvement over the 8-bit ADCs included on every Arduino.
The boards communicate with the Raspberry Pi over an I2C serial bus using a neat stackable header. In theory, it should be possible to use several of these boards and measure dozens of analog channels, but we’ll leave a demonstration of that up to [Brian].
http://hackaday.com/2012/09/14/a-truly-professional-raspi-analog-input/
Much to the chagrin of hardware tinkerers, the Raspberry Pi doesn’t have analog inputs on its GPIO pins. Sure, you can blink a LED with just a few console commands, but reading sensors with a bone-stock Raspi requires a little additional hardware. [Brian Dorey] just released a board that allows for 8 analog inputs (http://www.briandorey.com/post/ADC-Pi-Raspberry-Pi-I2C-Analog-to-Digital-Converter-boards-available-to-buy-online.aspx) on the Raspberry Pi with a 16-bit resolution that is much higher than any Arduino-based build.
[Brian]‘s build is based on an earlier, similar iteration (http://hackaday.com/2012/07/25/raspberry-pi-keeps-tabs-on-your-solar-power-setup/) of a Raspi analog board we saw last July. Like the previous version, the new professionally made PCBs use a pair of Microchip MCP3428 analog to digital converter. These ADCs are able to sample four channels at a resolution of 16 bits; a vast improvement over the 8-bit ADCs included on every Arduino.
The boards communicate with the Raspberry Pi over an I2C serial bus using a neat stackable header. In theory, it should be possible to use several of these boards and measure dozens of analog channels, but we’ll leave a demonstration of that up to [Brian].
http://hackaday.com/2012/09/14/a-truly-professional-raspi-analog-input/