Technology and experience from building products and putting them to work in the field.
59 reviewed posts
InsightsThirty sensors on one shared LoRaWAN gateway, and a node that would not join. With no CRC error to go on, the answer turned out to be the sync word set by a single toggle.
InsightsThe radio worked, but the sensors were in the field. A PC program that answers like one turned up four contradictions in the protocol document and a timer bug that split good frames in half.
InsightsCalling each device in turn fixed the collisions but cost 42 seconds a round, until we stopped waiting for replies. Plus the uplink monitor and the configuration tool built along the way.
InsightsThree wrong theories built on partial logs, and then a line-by-line comparison of the full record explained all thirteen uploads at once.
InsightsFrom cutting the enclosure to data that never reaches the server, five posts on a LoRaWAN sensor network - every one of them starting with a signal that said everything was fine.
InsightsAn automated clearance check that reads 0 mm3 is not the same as a case you can build. Five assembly failures, and the worst was a check that ran perfectly and reached the opposite conclusion.
NewsWhen the RP2350 Touch LCD 3.5 will not boot or the upload port cannot be found, unplug USB-C, hold the BOOT button, and reconnect the cable to enter USB download mode.
NewsAn RP2350 touch LCD timer that starts its MM:SS countdown only when the inverter is confirmed running - not when START is touched - and handles the STOP command and actual-stop check when time runs out.
NewsA horse-riding machine controller built with the 3.5-inch RP2350 touch LCD, with one manual mode, 11 program modes, 10-stage speed profiles, and RS485 Modbus RTU inverter control.
NewsRUN/STOP and speed control of an inverter over RS485 Modbus RTU, with the RP2350 touch LCD graphing only the speed the inverter actually reported - not the commanded value.
NewsCopying a TTF file into an Arduino project does not put Korean text on a TFT LCD. Here is how we converted only the glyphs and sizes the screen needs into bitmap data for the RP2350 Touch LCD 3.5.
NewsInstead of playing a video, we cycle three PNG frames and redraw only the region where the horse moves, cutting flicker on the ST7796 LCD.
InsightsAn unrouted net is not a conclusion but the starting point of the next investigation. Measuring in coordinates, suspecting the tool, unifying the pass criteria, and finally putting the placement choice itself inside the loop.
InsightsNine posts on PCB design automation, from generating the schematic to reaching DRC 0, collected on one page in the order the problems appeared.
Field NotesA field installation connecting straight, curved, and inclined conveyors and controlling each module through Wi-Fi and a PC integrated control UI.
NewsEvery time we scaled an 8-channel board to 16 channels, we had to redo the schematic and artwork. To cut the repetitive work, we introduced AI automation and built a library and pipeline.
InsightsReading PADS ASCII coordinates as 1nm made the parts, the traces and the board all 1.5× too large together, so every internal consistency check stayed green while the object was wrong.
InsightsA backslash that invalidated an entire file, pad fields shifted by one slot, and a 3D model rotation we guessed wrong three times - what we hit while moving 1,214 footprints and 857 symbols into a KiCad library.
InsightsThe 45° rule, staircases and antennas - none of which DRC catches - each needed a checker of its own, and the per-layer routing directions had to be injected straight into the DSN file.
InsightsIf the measurement changes the subject, it is not data. How we caught a check command rewriting the board and a fixer script shaving trace widths to turn DRC green, then measured our own shipping boards for the real numbers.
Insights12.9 bends per net and a detour ratio up to 3.0× said what the gates would not: a 16-channel board was being crammed onto two layers. How we moved it to four and re-injected the per-layer directions.
InsightsThe longest stretch in automation is not the first 90 percent but the last single item. Ranking the metrics as shorts over unrouted over clearance, and solving a blocked spot with a transaction that moves the wall.
InsightsDRC 0, unrouted 0, shorts 0, measured five times with the same result five times. The closing round that took arbitrary angles to zero, plus the seven ways our own tools lied along the way.
InsightsThe metrics we measured passing is no evidence that the items we did not measure are correct. The schematic, label and angle gaps a review exposed after we called the board done, and the gates built to close them.
NewsLadder on one side, screens on the other, and one rule holding them together - the values live in the PLC and the HMI only reads them and draws them.
NewsA compact PLC where ladder and C# share the same memory, with AD-4, DA-4 and IO-8 expansion boards on a CAN bus - validated by four games running out of one project.
InsightsNo new parts, just the beer lever again. The design looked elegant on paper and played badly, and the work was translating four vague impressions into four exact numbers - tension, fish stamina, hooking, and haptics.
InsightsFrom one lever to a cabinet holding four games, seven posts collected on one page - in the order the parts arrived and the games followed them.
InsightsThe input device picked the game again: an analog joystick meant a vertical scrolling shooter. Climbing a night sky, shooting enemies, and getting stronger on pickups - plus a memory remap, a broken cause and effect, and an interpolation fix.
InsightsThe ERM vibration motor promised in Part 2 is installed and buzzing, but pulling the lever further changed nothing. After two wrong theories we stopped guessing, logged the actual values, and found the output window was the problem.
InsightsThe title screen became a game select menu and blackjack became game two. A house rule deals the dealer a card every time you take one, and inheriting the first game's leaderboard and comms layer cut the build time in half.
InsightsA full day spent making the HMI screen feel alive: five animations, a pub background drawn in code, and a bartender that took four failed shape-built bears before one AI handed the drawing to another.
InsightsPart 2 of the arcade cabinet. A ball lever modeled parametrically in Blender and printed on a 3D printer, and a Pro Controller haptics transplant that failed - one photo of the real part overturned the whole design.
InsightsThe Pi Zero 2 W is sold out and the Luckfox Lyra Zero W is the substitute - but is it fast enough? Same benchmark, same .NET version, both boards. On paper the Pi should have won, and the clock said otherwise.
InsightsThe Raspberry Pi Zero 2 W at the heart of ZPi Controller is sold out. We picked the RK3506B-based Luckfox Lyra Zero W as a replacement and actually moved onto it, from flashing the image to rebuilding the kernel and running real CAN control.
InsightsRoot Bear is a Playdate game about turning a crank to pour the perfect root beer. We moved it onto a physical potentiometer lever and a touch panel, and by the end of one day the inside of the cabinet was genuine plant equipment.
NewsAn IP tells you nothing about which Pi you are looking at. Here is the active scan that finds them and the MAC-keyed nicknames that survive a reboot.
Field NotesThe real danger on a stage is not missing information - it is pressing the wrong channel or trusting a device whose link has dropped. The screens were designed around that.
NewsAn industrial HMI does more than draw screens: it talks to the plant floor, records what happens, raises alarms, and runs control logic. Here is the SENVAS Designer and SENVAS Runtime pair that does it on SENVAS Touch.
NewsPort forwarding, TeamViewer and self-hosted OpenVPN each come with a catch. SENVAS Touch solves industrial HMI remote access with a WireGuard-based Tailscale mesh VPN and Funnel HTTPS that opens only on demand.
NewsThe foundation layer of an industrial HMI device, the touch management launcher, is a .NET 9 Blazor Server app. The kiosk welcome screen, the web console and remote access are all the same app; the operator HMI runs on top of it.
NewsDevices work the moment you plug them in, but somebody still has to remember what runs where. One TXT convention and one tray app removed that chore.
NewsSeven posts on building an industrial controller out of a Raspberry Pi, collected on one page - from the hardware and the AI HMI through the debugging traps, boot time, and what comes next.
NewsAn industrial HMI touch device you can carry into a factory, a farm, or a power plant, plug in, and use. Kiosk auto-boot, network discovery, remote management, AI integration, and automated app deployment at a glance.
NewsZPi Controller pairs a Raspberry Pi Zero 2 W with a 4-input/4-relay board and runs .NET 9 plus Blazor on top. Part 1 walks through Modbus TCP/RTU, the browser rule editor, hosted user programs and the AI-generated operator HMI.
NewsBuild a full-screen industrial HMI for a Raspberry Pi PLC just by talking to Claude. The workflow lives inside the MCP tool description, and SSE auto-reload plus version rollback stay on the server side.
NewsConnecting a Raspberry Pi PLC to Claude Desktop should take one double-click. Getting there meant fighting encoding traps, cmd parser quirks, PowerShell escaping and three ways of launching Claude that did not work.
NewsA mistyped Modbus port that killed the web UI in an infinite restart loop, an avahi reload that keeps advertising the old hostname, and a C# regex replacement where $1 silently becomes $15 - with the broken and fixed code side by side.
NewsWiFi credentials that vanish after a reboot and a boot sequence that stalls for a full minute are both first-impression problems on a Raspberry Pi PLC. This is how we backed up credentials ourselves and dropped boot time to 33 s.
NewsMQTT as the top priority, WebSocket for a real live monitor, alarms and notifications, and ZViews the AI generates from a user program manifest. The v2 roadmap for this Raspberry Pi PLC and the closing post of the series.
NewsA single-page ZView, 10 KB of HTML, showing an upstream Modbus master driving four outputs and reading four inputs back. The bit matrix on screen catches byte swaps and wrong bit positions instantly.
InsightsOne Raspberry Pi turned into a shared uploader, so a firmware change no longer means carrying a laptop and a USB cable over to the machine.
InsightsThe design tools were never opened. The brochure was written in HTML, exported from Chrome, outlined in Ghostscript, and refined one instruction at a time.
Field NotesPress the wrong switch on a stage and a set misbehaves. Building a panel where a mistake is obvious took four visualisation rewrites and five rounds of GPIO conflict.
Field NotesA teaching kit becomes an industrial line: no phone in hand, cumulative counts on screen, and a wired link whose loss is actually visible.
Field NotesCoil bit packing, a black MJPEG screen and a pump that ignored its auto-stop - the three troubleshooting stories behind an indoor smart farm on one touch panel.
Field NotesFour LDRs give the direction error as a vector, two servos follow it, and a 7-inch panel shows the charge. The jitter fix and seven deployment rounds are the interesting part.
InsightsThree print-ready STLs and one design abandoned after seven rounds of corrections. The workflow, the parametric structure, and what went wrong.
NewsFrom an empty solution to v1.2.0.5 in seven days. The feature set, seven troubleshooting highlights, and the AI coding patterns that made the week possible.
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