Goldmine LCD with dsPIC board

PCB Front PCB Back

PCB Plots (front / back)

Front Back

Hardware (front / back)

Oscilloscope Oscilloscope

Simple Oscilloscope, Spectrum Analyzer

Spectrum Analyzer Demo Video

Hardware

This is a tiny board to make easy connection to the the inexpensive graphic LCD from Electronic Goldmine. You can find more info about this LCD at Tim's blog. The board provides the following features:

Potential applications include:

Firmware

dsPIC code for this will be developed using the freely available Microchip MPLAB IDE, including an assembler and GCC-based C compiler. Several archives of different firmware are here:

PC Board

This board is being fabbed at BatchPCB. It can be ordered directly from BatchPCB - cost is about $8/ea. You can find more here: dsPIC_lcd version 1.1 at BatchPCB.

Design files

Display Reliability

I bought 10 of the display modules from Goldmine. While testing the boards I had a lot of trouble getting them to work until I started cleaning the elastomer strips. I found that it's critical to clean the entire elastomer strip - both the side that touches the PCB and the side that touches the LCD glass. I used isopropyl alcohol and a cotton swab to wipe and dry the strips, as well as the PCB footprint. After learning this, all but one of the displays worked on the first try.

Incidentally, the one display that never worked was actually getting warm! Flipping the elastomer strip over, I spotted a scorched portion - probably a short between several adjacent power pins.

Status

06-22-09 - Start schematics.

06-30-09 - Layout complete - checking footprints.

07-01-09 - LCD footprint lines up with original. Added backlights.

07-02-09 - Tweaked some lines/rects that didn't line up right.

07-03-09 - Sent to fab. Should be back in ~3 weeks.

07-24-09 - Boards back. LCD fits footprint.

07-26-09 - Board assembled. Need wires for ISP on '12GP202 part.

07-29-09 - LCD won't initialize with Tim's config. On hold.

09-05-09 - Kenny Booth sends helpful startup hints out of the blue and I'm now able to draw on the screen. Also need to figure out why only one of my displays works.

09-07-09 - Built a second board & tested the remaining displays. Only one dud!

09-18-09 - C code for ADC driven bargraph & Oscilloscope apps

09-22-09 - '32GP302 board built - no haywires! Format update, spectrum analyzer app

09-24-09 - Added a font, extended spectrum analyzer and posted video

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Last Updated
:2009-09-24
Comments to:
Eric Brombaugh

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