port 65339 for ULA+ noread?

[tuFFo126]

According to the ULA+ specification, port 65339 is read/write. In sizif512 it looks like the port for registers (0-63) is write-only, it can only read from register 64 and only bit0.
I also have Just Speccy 128k with SLAM+128 and it matches the specifications there.

[UzixLS]

Reading isn't implemented because Sizif does not have enough cells inside CPLD to fit all ULA+ registers and instead use SRAM to store em. Reading would make things a much more complex.
Does it really required by some software or just for show?

[tuFFo126]

I understand correctly, what about false colors in ULA+ in the previous query?

[UzixLS]

Implemented with commit 8e09254
Now all ULA+ registers can be read.