Changes
/* Technical */
* Uses a 16KB ROM paged into memory at &0000.
* Uses a 8KB static RAM paged into memory at &c000-&dfff and repeats again at &e000-&ffff.
* ROM is paged into the range &0000-&3fff when the red button is pressed and the NMI vector is executed.
* When the black button is pressed, the ROM is paged into the range &0000-&3fff and executes it at &0000.
* Uses NMI
* Doesn't appear to capture the hardware state like the Multiface does. Code in the ROM reads the PPI hardware state, AY registers, and CRTC registers 12,13,14 and 15 and stores there values and which it restores them laterwhen resuming the program.
* When a write happens to their RAM it appears to write through to the RAM behind??
* Menu code is at offset &3810 and is copied into RAM at &A200.
* Uses port FBF0 (output), FBFF (input). Don't know the exact functions yet.writing FBF0 decoding is: 1111 1011 1111 00xx FBF0 output: bit 0 to fbf0 disables it's internal is ram enable/disable state bit 1 is romenable/disable state bit 2 is A10 on RAM bit 3 is A11 on RAM bit 4 is A12 on RAM bits 5-7 are not used.
* The same plastic case is used by the Spectrum version of this interface.
