====== Poisk-1 programming ======

===== Port 68h: Display Mode =====

<code>
7  bit  0
---- ----
r?pi nbbb
| || ||||
| || |+++- Mirrored from port 3D9h by BIOS (background color?)
| || +---- 0: NMI enabled / 1: NMI disabled
| |+------ Mirrored from port 3D9h by BIOS (high intensity foreground?)
| +------- Mirrored from port 3D9h by BIOS (palette?)
+--------- 0: 320x200 / 1: 640x200
</code>

===== Port 6Ah =====

<code>
7  bit  0
---- ----
???? ????
</code>