The Beta 128K Interface Disk for ZX Spectrum
the schematic and PCB for this interfaz, make in KICAD Including gerber files to direct order, the PCB is just 15x10cm.
THIS IS WORK IN PROGRESS.ACTUALY THIS INTERFACE DO NOT WORK!!!!! BE AWARE
NOT FOR USE, THIS IS ONLY A MOCKUP, WORK IN PROGRESS
(C) 2018 Alvaro Alea Fernandez.
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
http://creativecommons.org/licenses/by-nc-sa/4.0/
BOM is probably not acurrate, gerbers have names wrong.
GAL code is not checked
Even this interface provide a back conector for other interfaces, it do not provide a good IORQ signals, so can be incompatible with other interfaces that original interface is working good.
This board hide the serial port on +2.
The Advantege of this interfaz over the original are:
-
4 Banks of ROM, so you can swap between diferent versiones of TR-Dos. selectable by dip-switches (TR-DOS 5.03 and 5.04T with fixed, TR-DOS 6.04 & velesoft 5.03 with monitor.
-
Posibility of use crossed and plain floppy cable, and invert Drive 1 and Drive 2, very usefull if you have a Gotek and a real floppy.
-
Jumper for swap D0 & D7 (because some roms are distributed with this bits swapeed)
