Prototyping techniques
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
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