I would suggest to build a cheap and easy development environment only to fit your current requirements and which was near to your production planning. This save a lot of thinking, learning, developing and money.


The Cygnal parts are nice, but only if you want to use them also in practice. Otherwise you can have many trouble, because the instruction timing was fully different to standard 8051 parts.


Also any development board with external code memory should be omitted, if you want to use derivates with internal code in practice.
Such external code memory can cause many trouble, because it exclude P0, P2, P3.6 and P3.7 from usage as general purpose I/O.

If you want to use external code regardless, please watch, that some new 8051 derivates are damned fast. Then selection of fast and expensive EPROM / Flash and four-layer-pcb can be a must.

Especially for developing in harsh environment internal code was many times better to rule.


Dinosaurs like 8255 schould be omitted in any case.


Peter