Small improvement in circuit: part of RAM memory controller:

Just to break the inertia in this part after maybe two months...

Tetris game in the 8x8 led matrix is almost on Alpha version. It's working fine, but need performance improvements to be more playable. Logisim in my computer (Core i7/quad core/8gb) is only able to achieve around 2-3 KHz. Windows monitor shows ~25% of CPU used, which makes me think Logisim don't use any kinf of parallelism (not criticising at all, it's free and was only possible by the good will of author).