On the Subject of Diffusion

Solving a solution. That's a strange thing to say.

The module displays 12 coloured liquid compartments that can contain some concentration of solution A (red) and solution B (blue). However, diffusion happened and for each compartment some of the liquid has been shared among neighbouring compartments. To solve the module, find out what the initial configuration was of the solutions.

Highlighting a compartment will return some information about it on the central display. The two digits at the top are the concentrations of solution A and B respectively, ranging from 0 to 4. The character at the bottom shows your current entry for that compartment, being A, B, or neither, which is labeled as 0. This value can be changed by pressing the compartment.

The module started with compartments being filled with the highest concentration (4) of A, B, or neither. Now one iteration of diffusion occurred.

Diffusion goes as follows: Each square gives a quarter of its concentrations to its neighbouring cells and keeps half of the concentrations to itself.

Usually only one solution appears, but any valid solution will be accepted. This module automatically solves upon entering a valid solution and does not strike.

All possibilities
A\B 0 1 2 3 4
0 000 00B/B00 B0B/0B0 0BB/BB0 BBB
1 A00/00A B0A/A0B AB0/0BA ABB/BBA
2 A0A/0A0 BA0/0AB BAB/ABA
3 AA0/0AA AAB/BAA
4 AAA