Components
For the basic system, all the chips are available from major suppliers, though some are not available in the LS format. The table below gives details of the speed and power requirements, it is from the Digital Logic Family Selection Matrix.
You should be able to mix the various TTL technologies but out of an excess of caution, it is best to stick with just one. Mixing faster a slower should not be a problem at the base speed but if you try and overclock you may run into a problem with the slower technology.
A couple of the transistors are easiest and cheapest to get via EBAY or someone like Cricklewood Electronics rather the DigiKey or Mouser. The difficult to find Crystal was readily available from Cricklewood as £1.80 inc VAT see.
The 74AHCT166 is difficult to get hold of and id expensive however the slower speed should not cause a problem as it needs to be clocked at 6.5MHz regardless of what you can get the CPU too so the LS or ALS version should be fine.
Searching eBay with terms like Z80 homebrew can produce some interesting sources of items like the KIO when needed, though what you likely to need use eBay for is the memory chips you also need to find someone who can burn the ROMs for you, as they use a higher voltage than most USB devices can handle. In any of the versions from ACE2NOKBV2MK2 onward I will try to use more modern RAM and ROM that can be easily sources and programming.
The 7400 series is extensive and with some of the very fasts and energy-efficient versions likely to be around for a while. It is useful to a look at the list of chips available. Keep in mind that in addition to Texas instruments NXP, Nexperia, Onsemi, Diodes also make 74 series, TI provides some training information here and some sites like All About Circuits can provide input from experts.
A couple of the transistors are easiest and cheapest to get via EBAY or someone like Cricklewood Electronics rather the DigiKey or Mouser. The difficult to find Crystal was readily available from Cricklewood as £1.80 inc VAT see.
The 74AHCT166 is difficult to get hold of and id expensive however the slower speed should not cause a problem as it needs to be clocked at 6.5MHz regardless of what you can get the CPU too so the LS or ALS version should be fine.
Searching eBay with terms like Z80 homebrew can produce some interesting sources of items like the KIO when needed, though what you likely to need use eBay for is the memory chips you also need to find someone who can burn the ROMs for you, as they use a higher voltage than most USB devices can handle. In any of the versions from ACE2NOKBV2MK2 onward I will try to use more modern RAM and ROM that can be easily sources and programming.
The 7400 series is extensive and with some of the very fasts and energy-efficient versions likely to be around for a while. It is useful to a look at the list of chips available. Keep in mind that in addition to Texas instruments NXP, Nexperia, Onsemi, Diodes also make 74 series, TI provides some training information here and some sites like All About Circuits can provide input from experts.
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