The HEX6-BLE Server.
Six lines of light, one living memory.

A palm-sized central brain for green homes, ADUs and farms. Six laser channels and a fungal memristor feed HEX [PI], which forecasts the home's energy and schedules its battery, heat pump and loads. Built from about $175 of parts.

Components

drag to rotate

Glass domeSealed chamber that keeps the mycochip dry and stable.

MycochipDehydrated shiitake memristor with six probe electrodes.

Six optical linesOne 650 nm laser and one photodiode per face; one hexagram line each.

Compute coreRaspberry Pi 5 running HEX [PI]; ESP32-S3 for timing; 24-bit ADC.

Resonant coilTuned coil for wire-free power to pods and neighbouring servers.

Hex shellGrown mycelium composite or printed shell, 150 mm across.

The idea

A memristor is decayed state you can hold in your hand.

HEX [PI] learns from evidence that fades at a fixed rate: every observation counts, and older ones count less. A fungal memristor does the same thing physically. Its resistance depends on the history of current that passed through it, and that memory relaxes over time. The server puts the two side by side: the mycochip keeps an analogue, biological record of the light and climate around the home, and HEX [PI] keeps the statistical one.

Each of the six faces carries one optical channel, so the six lines of a hexagram are six physical inputs. Their on/off pattern each second is the server's 64-state reading, the same encoding the engine already uses.

Signal path

01 · senseNatureSunlight, temperature, humidity, soil moisture, household current.

02 · receiveLightSix photodiodes read laser pulses from neighbouring servers and ambient light.

03 · imprintMycochipLaser-driven pulses write into the fungal memristor; a 24-bit ADC reads its state.

04 · decideHEX [PI]Calibrated probabilities for solar output and load swings, with the symmetry field.

05 · actHomeCharge, hold or discharge the battery; pre-heat, pre-cool; sign the record.

Bill of materials

Part	Role	Est. USD
Raspberry Pi 5, 4 GB	Runs HEX [PI], the scheduler and the ledger client	$60
ESP32-S3 board	Real-time laser timing, stimulus waveforms, sensor bus	$8
Mycochip, 2 × dehydrated shiitake	Fungal memristor; from Ohio State or grown in-house	$10
ADS1256 24-bit ADC + MCP4725 DAC	Read and write the memristor (DC to about 6 kHz)	$17
6 × 650 nm laser diode, ≤1 mW, plus 6 × BPW34 photodiode	The six optical lines, Class 2 or lower	$14
BME280, BH1750, capacitive soil probe	Climate, light and moisture	$11
2 × SCT-013 current clamp	Whole-home and solar circuit metering	$12
Resonant coil pair, 100–200 kHz	Wire-free power to pods and neighbouring servers	$10
ATECC608 secure element	Hardware key that signs every reading	$2
Small PV cell and supercapacitor	Radiant trickle supply and ride-through	$8
Hex shell: grown mycelium composite or PLA print, glass dome	Enclosure	$15
Wiring, PCB, 5 V supply		$8
Total per server	Volume pricing would cut this to roughly $90–110	$175

Prices are estimates at typical US retail for single units and should be checked at purchase.

Test plan

Six bench tests, each pre-registered with a control, so every claim the server makes can be checked.

T1 · week 1Memristor signatureSweep the chip with sine waves from 1 Hz to 5.85 kHz and plot current against voltage.Pass if the loop pinches at zero, matching the Ohio State result, and a plain resistor shows no loop.

T2 · week 2Light writes memoryPulse the lasers in set patterns and read the chip's resistance afterwards.Pass if the patterns are distinguishable from the chip state, and a sham (inert carbon disc) cannot do it.

T3 · week 2Decay rateWrite one pulse train, then log retention for 24 hours.Pass if the memory fades along a stable curve, which gives the chip's own λ to set beside HEX [PI]'s.

T4 · week 3Optical syncTwo servers exchange timing and state over the laser channels at 2 m.Pass if the bit error rate stays under 10⁻⁴ indoors and the clocks agree within 1 ms.

T5 · weeks 4–12Energy in a real homeAlternate days between HEX [PI] scheduling and a fixed timer schedule on the same home.Pass if grid energy and peak demand fall on HEX [PI] days, beyond what weather explains.

T6 · weeks 4–12Does the chip add signal?Forecast with and without the mycochip channel, and against a shuffled copy of it.Pass if Brier skill rises with the chip and does not rise with the shuffled copy.

Roadmap

Phase 1 · Q4 2026Bench serverTwo servers, tests T1–T4, with an Ohio State chip and an in-house chip.

Phase 2 · Q1 2027Home brainOne ADU live with battery and heat-pump control, tests T5–T6.

Phase 3 · Q2 2027Farm and block meshSeven servers linked by light; soil and greenhouse pods powered wire-free.

Phase 4 · 2027+Energy ledgerSigned readings anchor to a chain; homes trade verified surplus and savings.

Safety and limits

The lasers are 1 mW or less (Class 2 or lower) and aimed only along enclosed or above-head paths between servers. Control of the battery and heat pump goes through the manufacturers' approved interfaces, and a licensed electrician installs the current clamps. HEX [PI] and the mycochip forecast and schedule; the home's own protection devices remain in charge of safety.

Academic review

The full research overview: measured results, open hypotheses and the experimental programme, prepared for institutional collaborators.

Can't view the PDF? Open it in a new tab.

The HEX6-BLE Server.Six lines of light, one living memory.