May 24, 2013 AT 1:00 am

Raspberry Pi Chained Shift Registers #piday #raspberrypi @Raspberry_Pi


From Les Orchard’s flickr:

I need to blog about this. This photo includes:

* A Raspberry Pi with a T-Cobbler
* Two 74HC595 shift registers
* A 20×4 LCD display with negative RGB backlight (currently hard-wired to purple)

Put together, this is a Raspberry Pi running a Python script that uses 3 GPIO pins to control 16 outputs.

Driving the LCD itself is a dirty, dirty hack that fools some code from Adafruit into thinking it’s talking directly to GPIO pins, when really it’s talking to my shift registers.

It’s that last part which made me bounce in my chair – because I don’t quite yet understand how to talk to the LCD display, yet my hack worked the first time. (Albeit very, very slowly.) \o/

In the near future, I want to figure out how to control the red / blue / green backlight pins from the Raspberry Pi, in order to change colors on the display

Original post here.

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1 Comment

  1. Hey, I just finished a quick proof of concept project using about 10 different adafruit products, including the T-Cobbler and wanted to show it off. (not sure this is the best place to do so, but here it is)


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