Tomeu CapóIn version 1.1 modify address decoding circuit and replace "OR" logic gates to 74138 TTL decoder to switch between RAM/ROM and devices like: PIO, UART, VDP and SOUND Generator.
Otherwise, design an external decoder to other devices put an OR gate between /EN internal decoder 138 and /IORQ and A6.
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In this version also changed RESET circuit with 555, that have more stability than RC and Smith-Trigger NOT gate.
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