Seven-hex prototype

The prototype has one centre hex and six surrounding hexes:

             H2

        H1        H3

             H0

        H6        H4

             H5

Index	Position
H0	Centre
H1	Upper-left
H2	Top
H3	Upper-right
H4	Lower-right
H5	Bottom
H6	Lower-left

Electrical order

MAIN → H0 → H1 → H2 → H3 → H4 → H5 → H6

This fixed order lets software associate chain index with physical location. Changing cable order changes that association. Label connectors and hex locations consistently; chain position does not discover tile orientation. Orientation and local sensor numbering still need to be fixed in the mapping.

SDA and SCL are a shared bus, not seven independent serial data links. Each CHAIN_OUT connects only to the following hex's CHAIN_IN. There is no Nanoleaf-style neighbour discovery in this prototype.

Intended scope

The seven hexes provide 21 road inputs, 21 building inputs, seven land inputs, and seven robber-presence inputs under the current allocation. These are channel counts, not proof of complete geometric coverage of the seven-hex cluster. List the exercised positions explicitly in the eventual mapping.

Begin with reliable local sensing and display control, then enumerate the full chain, translate readings into global positions, and expose diagnostics. Early experiments can use an Arduino Uno, but the intended main controller remains ESP32-class and an Uno is not included in the purchase BOM.

See the prototype roadmap, BOM, and enumeration proposal.