2007-01-21

ATmega16 controller and DOG-M LCD module – can’t get it to work right

Posted in PlanetDebian, electronics at 22:57 UTC (+0000) by sven

Well, today I worked on a new little hardware project. It’s supposed to become open source (both schematics/PCB layout and software), but I want to work on it together with a close friend more or less exclusively for now. Anyway what it is going to become is a small controller board with a 2×16 character LCD module (DOG-M162 from lcd-module.de, an Atmel ATmega16, a small serial EEPROM, an IR transceiver, a USB port (featured by an FTDI USB2serial chip) and two relais outputs. The software will use the board as an external controller for Canon EOS* cameras (one output controlling the autofocus trigger, one the shutter trigger) with several “programs” which take a photo every X seconds or opens the shutter for a given amount of time (up to several minutes for night time photos).

Anyway, today we worked on the first prototype board and tried to get the LCD to work. First we tried a 3.3V setup for the board – our initial goal – and several software versions later, we used an oscilator and found rather disgusting signal edges, so we switched to 5V (all components used were 5V and 3.3V capable, except that the display needed a slightly different circuit with a capacitor replaced by bare wire and another removed). Now the signal edges looked fine and we tripple checked that all connections were as expected. But even after trying two different initialization routines from the web and writing an own one from the controller specs, we were not successfull. This is quite frustrating, so if anyone would be able to help here, please leave a comment or contact me by email.