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Indeed, I have decided to go for the 65816. Ill save the 6502 for when I need to make a small embedded system to do something more invisible (like controlling the lights).
The '816 doesn't require any more external parts than the '02 if you don't use more than the first 64K of memory space. An exception might be if you can get away with just a resistor and capacitor hung on the '02 for a clock source instead of using an external oscillator.
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One thing about the 512x8 Kb SRAM: I can't seem to find it in DIP format, only in TSOP and the such. Seeing as how the SBC-3 also uses that small format, I'm pretty sure they either don't make those sizes in DIP anymore, or just never really did.
I have some 512Kx8 SRAMs here in DIPs. I even stacked four on a DIP header to get 2Mx8, with a 74AC139 stood on edge at the end to select the right chip. You can see the stack in this picture:
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This board is actually two projects, with the five ICs at the right end being a circuit to let me use a VIA's serial port to put
raster graphics on an analog oscilloscope. It was cool the first time I was able to put a paragraph of text on a totally analog 'scope! It uses the Z-axis input to turn the beam off and on.
Jameco has the 512Kx8 DIP SRAMs at
here, so you know it's pretty basic stuff. I think I got mine at
Debco for a lot less.
If you can go down to 3V, you can get 2Mx8, but those are all SMT.
Aries makes adapters so you can use SMT parts with DIP sockets. [
Edit: Winslow ones are available at
http://uk.rs-online.com/web/c/?searchTe ... ra=oss&r=t. Thanks Ed for the notice.] There are other manufacturers too, but stay away from Ironwood which is many times as expensive and no better. Soldering just takes a lot of flux and a lot of solder, but not a tiny iron. A 1/8" chisel tip will be fine since you won't solder just one pin at a time. To start, solder just the end pins on one side, just enough to hold the IC in place. Bridges are ok for now. Then solder down the other row of pins, using lots of flux and lots of solder. It may be all one huge solder bridge, but that's ok to start. Then you hold the board vertically and slowly run the soldering iron from top to bottom, re-melting all the solder on that side. The excess will stay on the iron, not the IC, and there will be no bridges. Now go back and do the first side which until now was only tacked. Clean off the flux, and it looks like it was done by machine. Perfect. It really is surprisingly easy.