SCSI to IDE

So? You know as well as I do that the cost of the chip is not the major cost for a 1-off (or small run) project like this. Yes, the microocntroller may be cheaper, but : You might well have Z80s, EPORms, RAMs, etc in the junk box (I certainly do), but not the latest microcontroller You may well feel it's a lot easier to solder up a handful of DIL packages on stripboard than a fine-pitch SMD packge that requires you you to design a PCB first . This in turn may entail obtianign suitable CAD tools, something to run them on, and finding a PCB manufacturer (or buying the equipoment to do it at home). You may well know the assmbly language for the Z80, and have the assembler, etc. Not so fo rthe microcotnroller. It's a darn sight easier to debug something when you know what it should be doing and can see what it is doing. The former is much easier to determine for a Z80 than many modern processors (where the instructions are not necesarily executed one at a time in the order you expect). The latter is also much easier to do on a system with external program memory where you cvan conenct a logic analyser to the ROM address lines. If you want a design to last as long as the classic computer it's connected to, I would certainly go with the Z80 + memory solution. Z80s are very common. The microcontroller may be common _now_, but whata bout next year. There are som many fariants with different memory sizes, internal peripherals, etc that several times I've needed to find a replacement for something made a few years ago onlky to find that that particualr chip is rarere than hen's teeth. Oh, there are 'improved versions', but they are not drop-in replacements. I also feel that this idea of always making everything as cheap as possible is a big mistake. It seems to lead to poorly made products with all sorts of corners cut. As I have said many times before, I can think of plentyy of examples where the cost to do it properly would add perhaps \pounds 1.00 od xomponents. Say that translates into \pounds 10.00 by the time you've added in all the otehr costs. That increase in selling price would not have stopped me buying the product. But when I see how many corners havec been cut, I am not goign to be happy, I am not going to buy any more products from that company, I am goign to tell my friends to look elsewhere too. Anyway... If you employ me to desgin soemthing, then you get to specify the sort of devices to be used. If you want microcontrollers, or FPGA,s or... then fine. But if I am doing it for myself as a hobbyist, then I get to pick the devices I like best. -tony