The boards the software was written for.

A focus-stacking controller: an ESP32-S3 development kit drives a stepper through a plug-in driver module, advances the stage one step at a time, and fires an isolated camera shutter at each position. Panel buttons, an encoder, a 20x4 I2C display and a bottom limit switch complete it. This is the board used as the worked example throughout the software pages - the coverage analysis, the EMC findings and the test plan are all this board.

Test fixtureA bed-of-nails fixture plate is drawn for this board, located from its mounting holes, with the probe positions taken from the coverage analysis. Designed, not yet machined.

A TI ADS8588S samples eight inputs simultaneously at up to 200 kS/s per channel, read by a plug-in Teensy 4.1 and delivered over a single USB cable. Channels pair into four differential inputs in firmware.

A deliberate cost-down of the eight-channel board, derived from its rev A. The AD7606C-16 that rev A used is not stocked by LCSC or JLC, so this drops in the pin-compatible classic AD7606 instead: four BNC inputs sampled together, two pairs usable as differential channels, read by the same plug-in Teensy 4.1.

Enclosure3-D printed base, slide-in BNC panel and lid. 98 x 90 x 30.5 mm outside. Designed, not yet printed.

A hot front end that floats at neutral and divides L1, L2, L3 and PE into an AD7606; an isolation barrier of two extra-wide-body digital isolators and an isolated DC/DC; and a SELV side where a second AD7606 reads four current transformers on the same conversion edge. A plug-in Teensy 4.1 reads both converters and serves USB and Ethernet. Voltage and current are therefore simultaneous rather than interleaved, which is what makes real power on three phases worth calculating.

A carrier that turns an ESP32-S3 development kit into a usable small PLC: twelve digital I/O, twenty-four analog inputs through a 24-bit ADC module, and a wide-input buck-boost supply so it will run from whatever the machine has. MBLT PLC describes this board in full, rev A and rev B, as a build target.

An isolated differential probe and a two-channel interface that let SignalScope measure anything from logic levels up to 1000 Vrms through a sound card's line input. The isolation is a TI AMC3311 reinforced isolation amplifier behind a symmetric divider - one PCB, three populations for three voltage ranges.

EnclosureTwo 3-D printed cases - a probe pod case with panel binding posts, and an interface case with light pipes for the indicator LEDs. Designed, not yet printed.

A 138.2 x 131.6 mm two-layer board that turns one USB 2.0 High-Speed connection into eight RS-232 ports. A Microchip USB2514B hub feeds two FTDI FT4232HL bridges; each UART drives its own TI MAX3243E and a male DB9 wired as DTE, exactly like a PC's COM port. Ports A to D leave one long edge and E to H the other. It runs from USB, or from a 5 V adapter when the port cannot supply what eight transceivers want.

A 138 x 69 mm two-layer board that turns one USB 2.0 High-Speed connection into four RS-232 ports with full modem control. One FTDI FT4232HL provides all four UARTs, each driving its own TI MAX3243E and a male DB9 wired as DTE. The board is powered from USB and the host sees four standard FTDI serial ports - no hub, no driver to hunt for.

A 100 x 100 mm two-layer demonstration board: an Arduino Nano on sockets drives a roulette wheel of 37 LEDs and three status LEDs through five 74HC595 shift registers, reads four push buttons and sounds a buzzer. It exists so the apps, the ICT fixture and the documentation have something to be demonstrated on that is not the Z-Stack carrier - which is a real product and should not have to be the worked example for everything.

Test fixtureA bed-of-nails fixture plate is drawn for this board, located from its mounting holes, with the probe positions taken from the coverage analysis. Designed, not yet machined.

The all-SMD sibling of the TCRT5000 board. A Sharp GP2S700HCP - a 4 x 3 x 2 mm leadless package holding a 950 nm IR LED and a phototransistor side by side - replaces the through-hole sensor, so every part except the hand-fitted header can be placed by the assembler. The interface is unchanged: VCC, GND and an analog OUT on a three-pin header, 3.3 to 5 V.

A small board that sees objects in front of it. A Vishay TCRT5000L shines 950 nm infrared forward and a phototransistor beside it measures how much comes back; the board turns that into an analog voltage on a three-pin header. It is sized for an enclosure - two M3 holes - and for the panel: 11.4 x 28 mm is what lets 21 boards share one 100 x 100 mm panel.

A small carrier for the Pololu S18V20F5 buck-boost module, so one supply design can be dropped into any of the boards rather than redesigned each time. Takes whatever the bench or the machine offers and gives back a clean 5 V.

A two-layer adapter that plugs straight into an instrument's GPIB receptacle - or the piggyback side of a GPIB cable - through a right-angle 24-way plug. An Arduino Nano on sockets is the bus controller and the USB port; TI's SN75160B and SN75161B give the bus its 48 mA drivers, receivers with hysteresis and terminations. On the PC it is one COM port, speaking either the MB Lab device profile - so HardwareRTD puts a reading from a 1980s meter into an Excel cell with nothing else installed - or the Prologix '++' command set, for tools that already expect it.

A weighing front end that turns a platform of load cells into something the rest of this family can read. A DOIT ESP32 DevKit plugs into sockets; the HX711 24-bit converter, the four-cell combiner, the power path, a Nextion touch-display port, TARE and ZERO inputs and an opto-isolated set-point output are on the board. It takes four 3-wire half-bridge cells summed into one bridge, or a single full-bridge cell, plus a second bridge on the converter's other channel - and answers SCPI over USB and over Wi-Fi, which is what puts it on a bench beside everything else here.

An Arduino UNO shield with addressable LEDs and a buzzer. It is the simplest board here, which is exactly why it is the one used to demonstrate the whole flow end to end - netlist-as-code, generated schematic, ERC and DRC gates, test coverage, Gerbers and a JLCPCB-ready BOM.