This is a handy device for prototyping, etc... It's a hexadecimal keypad (0..9, A..F) that outputs the hexadecimal value on 4 digital binary lines (one nibble). It has both active high and active low output (so it'll work for any system), as well as active high and active low strobe outputs for when the data is on the lines. I also added an on/off switch for convenience.
Here's the schematic: [attachment=1]
The video link below shows the device hooked up to some bargraph LEDs to show the output value and a couple of regular LEDs to show the strobe outputs. I built the key pad from an old keyboard I had. I basically cut out a section of the keyboard that was 4x4 keys, swapped out some keys to create the 0..9 and A..F, then hooked it up to the rest of the circuit. Sadly, the 0 key was lost, so it's not on there. But, the fun part is that you can see into the key itself to see how it works! :-)
Hi all! I searched the forum the best I could for this but couldn't find anything. Please excuse me if this has already been answered. I recently got a Bus Pirate v3.5 from the Free PCB Drawer (which I LOVE...thanks so much). It's not the 3.5a-SOIC version. I was wondering if there is anything special I need to do with the PCB to make sure it works properly...besides populate the components. :-) I ask because I noticed that on the new one that is being sold, there is a solder jumper that is needed. Anybody know if something needs to be done with this one to make it work or if there are any bugs in the design? Thanks! Chad
