Update: Connecting a LCD Panel to a Raspberry Pi

The backlight problem is fixed. My assumption was more or less right: The code for turning the backlight on/off is using POV to turn on the backlight in a smooth way. It seems that lcdproc is turning on and off the backlight during cycles. This switching is done faster than the smooth-on is finishing. At the end the backlight is flickering. I removed that part of the code from the firmware and the flicker was gone.LCD-Panel-Backlight-1Read more →


Free PCB built – LCD Backpack

Got it working. It wasn’t an electrical problem but a software one. I used the software from another built that was running the PIC with a 20 MHz crystal while I intended to run the board at 16 MHz. Therefore I had to adjust some settings in order get the oscillator set up correctly. Additionally some header were still missing. Below the nearly complete board. One header is still unpopulated.Populated LCD Backpack w HeaderOk…Now focussing on the software…Thanks DP

Free PCB built – LCD Backpack

After I received the PCB (PIC LCD Backpack) from Dangerous Prototypes it was lying around for some time because I wanted to finish some other projects first. I used that time for sourcing the required parts. Finally I started working on this and populating the PCB was quite quick. The result is not that bad. First checks showed that the power supply is doing fine and the first program upload (using a PICkit 3) was also successful.

Populated LCD BackpackWhen connecting it to the USB to a computer it turns out that the USB communication is not ok. The computer is recognizing that something is connected to the USB bus but is not able to identify the device (VID and PID zeroed). Well something is wrong here. I suppose an electrical problem. The PIC itself seems to be fine. At least I could debug it from the IDE.

Ok. Need to check if there’s any cold soldering joint…To be continued…