Here are two shots of a board I built for analysing hemoglobin oxygen absorption in blood. It is built on an Olimex P40 board with SMT resistors & caps on the underside. All the wiring is wire wrap wire soldered directly to underside of the board. There is a 16 bit ADC, Real Time Clock, LCD driver, variable amplitude LED drivers and a PIC16F877A. The Olimex boards are single sided so there is a tendency for pads to fall off after extensive modifications but they are excellent value for money for quick solutions to one-off problems.
A small Outline SOIC8 pack is on a sub protytype board.
I started out with the solderless breadboards. They are great while they are new and for prototyping small ideas. They get dust and other crap in the holes giving poor analog connections for 16 bit work. They are also relatively noisy with highish capacitance between pins. They rapidly reach a level of complexity where each new wire disturbs an existing wire and it gets very frustrating working out where any problems are. Full marks for skimask/mister e/whoever that just posted that monster solderless breadboard.
With prototype PCB services now so affordable, I have made myself three general purpose boards for PIC 40 pin packs. I use EAGLE (paid 100 x 160 mm version) and get these made in Malaysia at CustomPCB for about $10 each in plate through double sided. These have headers for switch inputs, LCD outputs, SOIC 8, SOIC 16 and a reasonable sized prototyping area.
HTH
Brian
Wow, you guys scare me.
I imagine the way the other prototypes shown in this thread started, was to take a board, plug in the parts in some manner that visually appealed to the builder, without regard to the circuits flow, then take a bunch of wires to hook up the different connections. Wherever they may be.
I suppose it's just different ways of doing things, but that's way to many wires for me.
This board is still a work in progress. But it shows a different way of interconnecting parts.
I don't even know that I could explain how to do it other than to say, you have to be able to visualize it in your head, before you put it on the board.
I try to put as many parts as possible, close to the parts they connect to. Minimizing wires (also called antenna) as much as I possibly can. Power busses are run on the top of the board with insulated wires.
It also keeps my cats from playing with the "antenna".
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2523&stc=1&d=120875099 6" />
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2524&stc=1&d=120875099 6" />
Ok, obviously not a PICPROTO18, but the ideas could still apply.
DT
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