Well, I designed the board, routed it, checked it, and sent it out to be fabbed…
Got my boards in and built one only to realize, I had made an error :(. I got my 5V and GND connections reversed. I don’t know how I did this, but I did. So here I sit with 10 boards with reversed power connections.
Being the person I am, I’m not going to let that stand in my way of seeing if the design works otherwise so Here is my build progress.
The blank board looks like this:
PCB TOP Side (Encoder, display, and Reset button mount on this side)
PCB Bottom (14 Pin Connector, Switch, .1uf Capacitor, Backlight Resistor, and Contrast Pot mount on this side)
And the close up of the connector showing pin 2 going to ground with Pin1 being VCC…. ARRGH
Well, I built the board anyway. For a temporary fix, I used a 10 pin connector on pins 5 thru 14 and a two pin connector for the power and ground (Pins 1 & 2) so I could reverse them. Once assembled, the board looks like this:
By now, you may be wondering what the reset button and switch are for. Well, it so happens that the Printrboard does not use three pins of the 14 in the connector. So, I designed this board to use those pins if a custom cable is used. On my board, pins 3 & 4 which are normally not connected, can be broken out to the two boot pins on the printrboard. Pin 9 which is normally not connected, can be broken out to the reset pin found in the 6 pin header on the printrboard. By doing this, you can reset the printrboard by pressing the reset button. Firmware can be uploaded by turning on the switch then pressing the reset button to enable firmware mode. Normal run mode is with the boot switch off. I haven’t yet tested these options, but they should work.
I’ve corrected the schematic and board files for my board, and will make them available shortly. They are licensed under Creative Commons Attribution-ShareAlike 4.0 International License.