... returning to 80's computing
These modules (#21, #31 and #41 or #44) give essentially the same functionality as RC2014/full monty/classic and Neoclassic, but the number of modules are reduced from 5 to 3, this is both for simplicity but also for system robustness. The Basic Modules also make the transition easier to a full robust CP/M system.
#21 Z80 CPU with integrated clock (up to 20Mhz)
#31 MC68B50P ACIA serial I/O module with integrated clock (7.3728Mhz recommended)
#41 Memory Module, using 64kb ROM divided into eight 8kb banks (selectable) and 32kb RAM.
Alternatively #44 can be used, dividing the 64kb ROM into two 32kb banks.
This system can be built, reusing ICs from the classic/full monty system. With this system it is easy to upgrade to full CP/M system. The memory module needs to be replaced with a 64kb RAM/ROM module and adding a storage system (CF drive).