An Enhanced MK14 - MK14E

Still under development -  everything on these pages should be considered provisional



The MK14 computer suffers from a number of shortcomings that make it increasingly difficult to build (as replicas) and then to upgrade:

So here is an enhanced design which overcomes those issues and also provides a much more flexible platform upon which future experimentation can be carried out whilst still being 100% compatible with the original SCIOS firmware, perhaps the next version of the MK14 that would have been if Sinclair had not then developed the ZX80 ?

 I have tried to use components that are still available and in keeping with the original.


Here are the highlights:

The main board also incorporates features that were left off the original - the Cassette Interface and Single Step function.


I've already mentioned that the expansion bus connector is a DIN41612, this can be connected to a 3-slot backplane which then allows for the addition of two further boards:

(Both boards still under development)


Follow these links for details of each of the boards: 

And here is the memory map for the complete system



The only thing that is missing is a QWERTY keyboard which is still in the planning stage !



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