# MakerIoT2020

> Maker & IoT ideas. Custom PCBs, ESP32, RP2040 and LoRa projects, from idea to an assembled board.

Open-source maker projects with schematics, custom PCB designs, firmware and build notes. Each project page has the full write-up, pictures and, where available, download files (Gerbers, code). Posts are numbered U1 (oldest) upwards.

## Topics

- [Custom PCB Design](https://www.makeriot2020.com/category/custom-pcb-design/): 69 projects
- [Arduino](https://www.makeriot2020.com/category/arduino/): 40 projects
- [Electronics](https://www.makeriot2020.com/category/electronics/): 36 projects
- [Breakout Board Modules](https://www.makeriot2020.com/category/breakout-board-modules/): 32 projects
- [PCBDesign](https://www.makeriot2020.com/category/pcbdesign/): 28 projects
- [ESP32](https://www.makeriot2020.com/category/esp32/): 26 projects
- [I2C Devices](https://www.makeriot2020.com/category/i2c-devices/): 25 projects
- [IoT Devices](https://www.makeriot2020.com/category/iot-devices/): 25 projects
- [ESP8266](https://www.makeriot2020.com/category/esp8266/): 18 projects
- [Raspberry Pi Pico](https://www.makeriot2020.com/category/raspberry-pi-pico/): 14 projects
- [IO-Extender-Outputs](https://www.makeriot2020.com/category/io-extender-outputs/): 13 projects
- [RP2040](https://www.makeriot2020.com/category/rp2040/): 13 projects

## Projects (newest first)

- [Elecrow CrowPanel PICO HMI 4.3" Display - Review](https://www.makeriot2020.com/elecrow-crowpanel-pico-hmi-4-3-display-review/): Review of the Elecrow CrowPanel Pico HMI 4.3-inch RP2040 touch display: specs, unboxing, a look inside and how well it works. (U145, 2024-12-12)
- [NeoPixel CAN-Bus Module with local control](https://www.makeriot2020.com/neopixel-can-bus-module-with-local-control/): A CAN bus NeoPixel module with local control, to light a car cabin from one controller: schematic, PCB, assembly and testing. (U144, 2024-10-27)
- [NeoPixel strip with built-in LDO](https://www.makeriot2020.com/neopixel-strip-with-built-in-ldo/): A NeoPixel strip PCB with a built-in LDO so the 5 V LEDs run from higher supply voltages: schematic, using the strip and manufacturing. (U143, 2024-10-27)
- [Assembly of the ATTiny1616 Can bus controller PCB](https://www.makeriot2020.com/assembly-of-the-attiny1616-can-bus-controller-pcb/): Assembling and testing the double-layer, mostly SMD ATtiny1616 CAN bus controller PCB, block by block. (U142, 2024-10-25)
- [ATTiny1616 Can Bus Controller PCB](https://www.makeriot2020.com/attiny1616-can-bus-controller-pcb/): An ATtiny1616 CAN bus controller PCB with buck and boost power, LiPo charging and ideal-diode supply OR-ing, all in functional blocks. (U141, 2024-09-25)
- [18650 Cell Boost Converter](https://www.makeriot2020.com/18650-cell-boost-converter/): A tiny boost converter for 18650 cells, an add-on for the single-cell charger, to power projects from one lithium cell. Design, assembly and tests. (U140, 2024-04-30)
- [Lipo Cell Charger Rev 2.0 - A Combination of various circuits](https://www.makeriot2020.com/lipo-cell-charger-rev-2-0-a-combination-of-various-circuits/): 18650 LiPo charger revision 2.0, fixing the weak points readers pointed out, by combining several proven circuits. PCB, manufacturing and assembly. (U139, 2024-04-30)
- [MAX40200 "Ideal Diode" Lipo Cell OR-ing prototype](https://www.makeriot2020.com/max40200-ideal-diode-lipo-cell-or-ing-prototype/): Testing the MAX40200 'ideal diode' to combine LiPo cells and mains power without diode losses: the evaluation circuit on a PCB, and results. (U138, 2024-04-30)
- [A Student designed ESP8266 Dev Board](https://www.makeriot2020.com/a-student-designed-esp8266-dev-board/): An ESP8266 dev board designed by a final-year high school student as a PCB design challenge: manufacturing, assembly and a gentle critique. (U137, 2024-01-26)
- [A Simple IoT Plant Watering Solution](https://www.makeriot2020.com/a-simple-iot-plant-watering-solution/): A simple ESP8266 IoT plant watering system designed with language students at a local high school: circuit, assembly, enclosure and code. (U136, 2024-01-25)
- [XIAO RP2040 Mouse Ver 3.0](https://www.makeriot2020.com/xiao-rp2040-mouse-ver-3-0/): Version 3.0 of the Seeed XIAO RP2040 mouse: all hardware bugs fixed and a first enclosure, with the PCB, assembly and firmware. (U135, 2024-01-25)
- [Assembling the Mushroom House Controller - Part 2](https://www.makeriot2020.com/assembling-the-mushroom-house-controller-part-2/): High-school students assemble the SMD mushroom house controller PCB they helped design, for the first time ever: the PCB, assembly and results. (U134, 2023-12-28)
- [Mushroom House Controller - Part 1](https://www.makeriot2020.com/mushroom-house-controller-part-1/): An ESP32 controller for an oyster mushroom growing house, a collaboration with Maesai Prasisart School in Chiang Rai: the site, classroom and PCB. (U133, 2023-12-25)
- [Single Cell Lipo Charger](https://www.makeriot2020.com/single-cell-lipo-charger/): A single-cell 18650 LiPo charger board for quick recharging and as a building block for a future power system: schematic, PCB and testing. (U132, 2023-12-19)
- [AI-Thinker AiPi Eyes S1 - Something interesting...](https://www.makeriot2020.com/ai-thinker-aipi-eyes-s1-something-interesting/): A look at Ai-Thinker's AiPi Eyes S1 board from their R&D pipeline, and thoughts on what this new module could be good for. (U131, 2023-11-26)
- [Xiao RP2040 Joystick Mouse - revision 2.00](https://www.makeriot2020.com/xiao-rp2040-joystick-mouse-revision-2-00/): Revision 2.0 of the Seeed XIAO RP2040 joystick mouse: what months of daily use taught, the parts used, the new PCB and testing. (U130, 2023-10-27)
- [MCP23008 Breakout](https://www.makeriot2020.com/mcp23008-breakout/): An MCP23008 8-bit I2C IO expander breakout, made while prototyping the XIAO RP2040 emergency mouse. Schematic, PCB, assembly and testing. (U129, 2023-10-24)
- [High Current P-Mos Driver](https://www.makeriot2020.com/high-current-p-mos-driver/): A high-current P-MOSFET driver with the IRF4905 for bright LED lights and other big loads: intended use, schematic and PCB. (U128, 2023-10-23)
- [Xiao ESP32S3 Media Device Prototype](https://www.makeriot2020.com/xiao-esp32s3-media-device-prototype/): A Seeed XIAO ESP32-S3 media device prototype for ESPHome: what the project does, what is on the PCB, manufacturing, assembly and testing. (U127, 2023-08-23)
- ["The Emergency Mouse" - A project born out of necessity](https://www.makeriot2020.com/the-emergency-mouse-a-project-born-out-of-necessity/): The Emergency Mouse: a Seeed XIAO RP2040 joystick mouse built late on a Friday when the real one died, from breadboard mess to custom PCB. (U126, 2023-07-28)
- [Multi-Purpose IO Card](https://www.makeriot2020.com/multi-purpose-io-card/): A multi-purpose IO card for prototyping: push buttons, rotary encoder, display and I2C expanders on one PCB, for Arduino, ESP32 and ESP8266. (U125, 2023-07-26)
- [Simple Smart Light Controller](https://www.makeriot2020.com/simple-smart-light-controller/): A simple ESP8266 smart light controller to automate lights and save energy in a rental house: PCB, configuration, software and testing. (U124, 2023-07-25)
- [LED COB Controller](https://www.makeriot2020.com/led-cob-controller/): An ESP8266 LED COB light controller running ESPHome: why COB LEDs, the PCB, schematic, configuration and software. (U123, 2023-07-20)
- [Variable Voltage Power Module](https://www.makeriot2020.com/variable-voltage-power-module/): A variable voltage power module with enough current for power-hungry ESP32 and ESP8266 projects: what is on the PCB, use and schematic. (U122, 2023-07-17)
- [An I2C Matrix Keypad](https://www.makeriot2020.com/an-i2c-matrix-keypad/): A 4x4 matrix keypad with its own I2C interface, so it needs 2 pins instead of 8 on Arduino, ESP32, STM32 or Pico. Schematic, PCB and assembly. (U121, 2023-06-27)
- [ESP32-S DEV Board - Rev 2.0](https://www.makeriot2020.com/esp32-s-dev-board-rev-2-0/): ESP32-S dev board in Arduino Uno form factor, revision 2.0: what changed from rev 1.0 and why, manufacturing and assembly. (U120, 2023-06-24)
- [A quick P-MOS MOSFET Driver Board](https://www.makeriot2020.com/a-quick-p-mos-mosfet-driver-board/): Why a P-channel MOSFET needs a driver from 3.3/5 V logic, and a quick P-MOS driver prototype board: the story, schematic and PCB. (U119, 2023-06-21)
- [A Reliable Matrix Keypad](https://www.makeriot2020.com/a-reliable-matrix-keypad/): A reliable 4x4 matrix keypad on a PCB with proper buttons instead of flimsy membranes: how matrix keypads work, assembly, testing and code. (U118, 2023-06-18)
- [ATMEGA4808 with CAN Bus](https://www.makeriot2020.com/atmega4808-with-can-bus/): An ATmega4808 development board with CAN bus hardware, part of a set of bench tools for CAN-controlled car gadgets. Schematic, PCB and assembly. (U117, 2023-05-28)
- [CAN Bus support with the ATTiny1616](https://www.makeriot2020.com/can-bus-support-with-the-attiny1616/): An ATtiny1616 board with CAN bus (MCP2515) as a cheap Arduino-compatible CAN node: what is on the PCB, schematic, manufacturing and assembly. (U116, 2023-05-25)
- [Stereo I2S Shield - The next iteration...](https://www.makeriot2020.com/stereo-i2s-shield-the-next-iteration/): Stereo I2S shield version 2 for the ESP32-S: the DAC on board instead of plug-in modules, the first version's mistakes fixed, assembly and tests. (U115, 2023-05-23)
- [My Own DC-DC Buck Converter](https://www.makeriot2020.com/my-own-dc-dc-buck-converter/): Designing my own DC-DC buck converter: why switch-mode beats linear regulators, choosing a driver IC, the design and PCB layout. (U114, 2023-05-22)
- [Breadboard Power Rail Bridge](https://www.makeriot2020.com/breadboard-power-rail-bridge/): A tongue-in-cheek, over-engineered breadboard power rail bridge with LEDs and extra headers, and what went wrong with the 'added features'. (U113, 2023-04-26)
- [Stereo I2S Shield for ESP32-S Dev Board](https://www.makeriot2020.com/stereo-i2s-shield-for-esp32-s-dev-board/): A stereo I2S audio shield for the ESP32-S dev board: add sound and music to projects. Software, manufacturing, assembly and the lessons learned. (U112, 2023-04-26)
- [Low BOM cost 4-cell 18650 Charger](https://www.makeriot2020.com/low-bom-cost-4-cell-18650-charger/): A low-cost 4-cell 18650 lithium charger module to charge several cells at once: prototype, schematic, PCB design and manufacturing. (U111, 2023-04-24)
- [Variable Breadboard Power Module](https://www.makeriot2020.com/variable-breadboard-power-module/): A variable breadboard power module improving on the fixed 3.3 V/5 V design: adjustable output, better heat sinking, schematic, assembly and setup. (U110, 2023-04-21)
- [ATMEGA4808 - An Improvement on my previous design? Or Not...](https://www.makeriot2020.com/atmega4808-an-improvement-on-my-previous-design-or-not/): A second ATmega4808 development card: what changed from the first design, whether it mattered, and an honest look at the result. (U109, 2023-03-27)
- [A complete ATTiny1616 Dev Solution](https://www.makeriot2020.com/a-complete-attiny1616-dev-solution/): A complete ATtiny1616 development board with UPDI programming, as an alternative to scarce ATmega328 chips: features, PCB and assembly. (U108, 2023-03-26)
- [Breadboard Power Module - Custom designed](https://www.makeriot2020.com/custom-designed-breadboard-power-module/): A custom breadboard power module that fixes the irritations of the cheap commercial ones: schematic and PCB. (U107, 2023-03-23)
- [Breaking out of the Chip Shortage - Attempt #3](https://www.makeriot2020.com/breaking-out-of-the-chip-shortage-attempt-3/): Chip shortage attempt #3: the ATmega4808 as an Arduino Uno/Nano replacement, on a prototype PCB with assembly, soldering and photos. (U106, 2023-02-26)
- [Breaking out of the Chip Shortage - Attempt #2](https://www.makeriot2020.com/breaking-out-of-the-chip-shortage-attempt-2/): Chip shortage attempt #2: the ATtiny1616, with more GPIO, flash and RAM, on a minimal breakout board. Programming, schematic and assembly. (U105, 2023-02-24)
- [Get Started with the ATMegaTiny202](https://www.makeriot2020.com/get-started-with-the-atmegatiny202/): Getting started with the ATtiny202 as a chip-shortage replacement for the ATmega328P: first prototype board, UPDI programming and PCB. (U104, 2023-02-22)
- [Small and Cheap UPDI Programmer](https://www.makeriot2020.com/small-and-cheap-updi-programmer/): A small, cheap UPDI programmer built on the CH340N for the new ATtiny and ATmega chips: schematic, PCB and assembled photos. (U103, 2023-02-17)
- [Multipurpose USB UART Module](https://www.makeriot2020.com/multipurpose-usb-uart-module/): A multipurpose USB-to-UART and UPDI module for programming ESP32, ESP8266, Arduino (ATmega328P) and new ATtiny chips. PCB and connections. (U102, 2023-02-14)
- [A Soft Start Circuit Experiment](https://www.makeriot2020.com/a-soft-start-circuit-experiment/): Testing a soft-start latching power switch instead of a mechanical on/off switch: schematic, how it works, load limits and problems found. (U101, 2023-01-29)
- [8Ch NMOS Breakout Module](https://www.makeriot2020.com/8ch-nmos-breakout-module/): An 8-channel N-MOSFET breakout, companion to the P-MOS board, for switching loads from Arduino, ESP32, STM32 or Pico. Schematic and PCB. (U100, 2023-01-27)
- [8-Ch P-Mos Breakout](https://www.makeriot2020.com/8-ch-p-mos-breakout/): An 8-channel P-MOSFET breakout to drive motors, RGB lights and other high-current loads from Arduino, ESP32 or Pico pins. Schematic, use and PCB. (U99, 2023-01-26)
- [Redesigning my MCP23017 breakout](https://www.makeriot2020.com/redesigning-my-mcp23017-breakout/): Second version of the breadboard-friendly MCP23017 I2C expander breakout: the issues found, what changed, pinouts and the new PCB. (U98, 2023-01-20)
- [Dual 555 Latching Switch Module](https://www.makeriot2020.com/dual-555-latching-switch-module/): A dual 555 latching switch module: two push-on, push-off channels on one board with very low current draw. PCB and photos. (U97, 2022-12-30)
- [555 based Latching Switch](https://www.makeriot2020.com/555-based-latching-switch/): A 555 timer as a push-on, push-off latching switch: how the circuit works, possible uses and a small breakout PCB. (U96, 2022-12-29)
- [AI-WB2 and XIAO RP2040 Combo](https://www.makeriot2020.com/ai-wb2-and-xiao-rp2040-combo/): Combining Ai-Thinker's AI-WB2 (BL602 RISC-V WiFi and BLE) with a Seeed XIAO RP2040 on one PCB: schematic, software and board. (U95, 2022-12-28)
- [Carrier board for SEEEDuino XIAO](https://www.makeriot2020.com/carrier-board-for-seeeduino-xiao/): A carrier board for the Seeeduino XIAO: XIAO specs and a PCB that turns the tiny board into an easy base for finished projects. (U94, 2022-12-26)
- [Useful ESP12E-DEV Prototype Shield](https://www.makeriot2020.com/useful-esp12e-dev-prototype-shield/): A prototype shield for the ESP-12E dev board, like the ESP32-S version with some changes: PCB design, schematic and photos. (U93, 2022-11-29)
- [RP2040 Scoppy Oscilloscope Analog Front End Shield](https://www.makeriot2020.com/rp2040-scoppy-oscilloscope-analog-front-end-shield/): An analog front-end shield for the Scoppy RP2040 oscilloscope: the recommended circuit on a PCB, with op-amp and Pico input protection. (U92, 2022-11-27)
- [An Easy RP2040 Logic Analyzer Shield - Scoppy Scope Part 2](https://www.makeriot2020.com/an-easy-rp2040-logic-analyzer-shield-scoppy-scope-part-2/): A Scoppy logic analyser shield with logic probes for the Raspberry Pi Pico carrier board: what is on the PCB, schematic and layout. (U91, 2022-11-25)
- [RP2040 Oscilloscope and Logic Analyser](https://www.makeriot2020.com/rp2040-oscilloscope-and-logic-analyser/): A cheap oscilloscope and logic analyser from a Raspberry Pi Pico with Scoppy: getting started, my setup and its limitations. (U90, 2022-11-25)
- [A versatile easy to use XIAO RP2040 LoRa Fusion](https://www.makeriot2020.com/a-versatile-easy-to-use-xiao-rp2040-lora-fusion/): XIAO RP2040 LoRa Fusion: a small board joining a Seeed XIAO RP2040 with an RA-02 LoRa radio. Features, specifications and PCB. (U89, 2022-11-21)
- [Easy to use ESP32-S DEV Prototype Shield](https://www.makeriot2020.com/easy-to-use-esp32-s-dev-prototype-shield/): A prototype shield for the ESP32-S dev board: move breadboard circuits to a permanent board without designing a new PCB. (U88, 2022-10-27)
- [ESP8266-12E in Arduino Form Factor](https://www.makeriot2020.com/esp8266-12e-in-arduino-form-factor/): An ESP8266-12E board in Arduino Uno form factor, a companion to the ESP32-S version: what is on the PCB, layout and assembly photos. (U87, 2022-10-22)
- [ESP32-S in Arduino Form Factor](https://www.makeriot2020.com/esp32-s-in-arduino-form-factor/): An ESP32-S board in Arduino Uno form factor so existing shields fit: the design, schematic and PCB. (U86, 2022-10-16)
- [A RISC-V IoT Development Board](https://www.makeriot2020.com/a-risc-v-iot-development-board/): A prototype RISC-V IoT development board around a new chip under NDA: the steep learning curve, the PCB and first results. (U85, 2022-09-30)
- [RaspberryPi Pico Carrier PCB](https://www.makeriot2020.com/raspberrypi-pico-carrier-pcb/): A Raspberry Pi Pico carrier PCB with the pin labels on top where you can read them, plus headers for expansion shields. (U84, 2022-09-25)
- [USB Power Supply Module](https://www.makeriot2020.com/usb-power-supply-module/): A homemade multi-port USB power supply module with the features cheap chargers lack: why build it, schematic and PCB. (U83, 2022-08-28)
- [An SMD Breadboard](https://www.makeriot2020.com/an-smd-breadboard/): An SMD breadboard PCB: prototype with surface-mount parts without the noise, stray capacitance and loose wires of a normal breadboard. (U82, 2022-08-28)
- [ATMega328 I2C Base Board](https://www.makeriot2020.com/atmega328-i2c-base-board/): A smaller two-slot ATmega328P I2C base board, a cut-down ESP-12E I2C base card for projects where enclosure space matters. Schematic and PCB. (U81, 2022-08-25)
- [PWM Controller with R/E](https://www.makeriot2020.com/pwm-controller-with-r-e/): A compact PWM controller PCB with rotary encoder, shrinking the ESP-12E I2C base card system to fit in an enclosure, built for an air-assist blower. (U80, 2022-08-19)
- [Using a Rotary Encoder](https://www.makeriot2020.com/using-a-rotary-encoder/): Arduino-style code for reading a rotary encoder, written for the ATmega328P PWM controller card and easy to adapt to Arduino, ESP32 or ESP8266. (U79, 2022-08-08)
- [I2C IO Card for ESP-12E I2C Base Card](https://www.makeriot2020.com/i2c-io-card-for-esp-12e-i2c-base-card/): An I2C IO card for the ESP-12E base card: two optically isolated relays and six GPIO pins on one address-selectable PCF8574, with mains cutouts. (U78, 2022-07-28)
- [ATMega 328P Based PWM controller Card](https://www.makeriot2020.com/atmega-328p-based-pwm-controller-card/): An ATmega328P PWM controller card: an add-on for the ESP-12E I2C base board or a standalone Arduino Nano-compatible board with level conversion. (U77, 2022-07-27)
- [VC-01 and VC-02 Offline Voice Module](https://www.makeriot2020.com/vc-01-and-vc-02-offline-voice-module/): A first prototype PCB for Ai-Thinker's VC-01/VC-02 offline voice modules: schematic, testing and controlling real devices by voice, no cloud. (U76, 2022-07-26)
- [True OFFLINE Voice Assistant](https://www.makeriot2020.com/true-offline-voice-assistant/): A truly offline voice assistant with Ai-Thinker's VC-01/VC-02 modules: no cloud, custom firmware, controlling real hardware, and a prototype PCB. (U75, 2022-07-21)
- [ESP-12E I2C Base Card](https://www.makeriot2020.com/esp-12e-i2c-base-card/): The ESP-12E I2C base card: 4 expansion slots with 12 V, 3.3 V, I2C and IRQ lines, the main board for the ESP-12E card system. (U74, 2022-07-18)
- [ESP-12E Card](https://www.makeriot2020.com/esp-12e-card/): The ESP-12E card: an ESP8266 MCU card for a modular system with a main board and plug-in expansion cards, like a desktop PC. Schematic and PCB. (U73, 2022-07-13)
- [iPCB-DFM - Intelligent PCB DFM](https://www.makeriot2020.com/ipcb-dfm-intelligent-pcb-dfm/): iPCB-DFM, PCBPartner's free design-for-manufacturability Gerber checker: what DFM is, why use it, its features and requirements. (U72, 2022-07-01)
- [Robotic Toy Car - Part 6](https://www.makeriot2020.com/robotic-toy-car-part-6/): Robotic toy car part 6: an ESP8266 remote control unit using ESP-NOW, with its schematic and custom PCB. (U71, 2022-06-29)
- [Robotic Toy Car - Part 5](https://www.makeriot2020.com/robotic-toy-car-part-5/): Robotic toy car part 5: the power distribution PCB, built around an MH-CD42 LiPo charge and boost module, with schematic and board. (U70, 2022-06-28)
- [Fix Driver Issues with CH340G on Ubuntu 22.04 LTS ( and possibly other Linux Distro's)](https://www.makeriot2020.com/fix-driver-issues-with-ch340g-on-ubuntu-22-04-lts-and-possibly-other-linux-distros/): Fix CH340G USB-serial ports not working on Ubuntu 22.04 for Arduino, ESP32 and ESP8266: kernel update, CH34x driver build and the conflicting service. (U69, 2022-06-23)
- [Robotic Toy Car - Part 4](https://www.makeriot2020.com/robotic-toy-car-part-4/): Robotic toy car part 4: PCB side panels full of 555-timer flashing lights, and why the 'robot' still gets a remote control. (U68, 2022-06-23)
- [Adding flashing lights to the Robotic Toy Car Project](https://www.makeriot2020.com/adding-flashing-lights-to-the-robotic-toy-car-project/): Robotic toy car part 3: flashing lights driven over I2C, useful for fun and as debug signals, with schematic, code and PCB. (U67, 2022-06-16)
- [Robot Toy Car - The Next steps](https://www.makeriot2020.com/robot-toy-car-the-next-steps/): Robot toy car part 2: the ESP8266 controller board, problems found so far, software, and how the car will be controlled. Custom PCB. (U66, 2022-06-09)
- [Ai-Thinker Ra-08 LoRaWAN](https://www.makeriot2020.com/ai-thinker-ra-08-lorawan/): Ai-Thinker's Ra-08 and Ra-08H LoRaWAN modules: ASR6601 with Cortex-M4 and SX1262 transceiver, frequency bands, specs and applications. (U65, 2022-06-02)
- [A breadboard friendly MCP23017](https://www.makeriot2020.com/a-breadboard-friendly-mcp23017/): A breadboard-friendly MCP23017 I2C IO expander breakout board: features, schematic, how to use it, and ordering the PCB. (U64, 2022-05-28)
- [Give an old toy car new life...](https://www.makeriot2020.com/give-an-old-toy-car-new-life/): Turn an old toy car into a robot: controlling DC motors from a microcontroller, direction control and a custom motor driver PCB. Part 1. (U63, 2022-05-27)
- [ESP32-S Card Module](https://www.makeriot2020.com/esp32-s-card-module/): An ESP32-S card module with a standard 2x20 pin interface, the first of a family of plug-in MCU cards for one shared baseboard. Schematic and PCB. (U62, 2022-05-23)
- [Level Converted CAN-BUS Module](https://www.makeriot2020.com/level-converted-can-bus-module/): A level-converted CAN bus module that works with both 3.3 V and 5 V microcontrollers: schematic, how it works, Arduino and ESP32 examples. (U61, 2022-05-21)
- [Battery Backup for your Pi Zero (W)](https://www.makeriot2020.com/battery-backup-for-your-pi-zero-w/): A cheap battery backup board for the Raspberry Pi Zero (W) that protects the SD card from power cuts. Design, how it works and PCB files. (U60, 2022-04-27)
- [Compact Remote Alarm Transceiver - Part 2](https://www.makeriot2020.com/compact-remote-alarm-transceiver-part-2/): The TXS0108E bidirectional 8-bit level shifter explained and used on the LoRa remote alarm transceiver, with the finished PCB. (U59, 2022-04-25)
- [Compact Remote Alarm Transceiver - Part 1](https://www.makeriot2020.com/compact-remote-alarm-transceiver-part-1/): A compact LoRa remote alarm transceiver with ATmega328P: trying LM317 regulators and dedicated logic level conversion, with PCB manufacturing. (U58, 2022-04-18)
- [Special Limited Offer - Get your PCB for only $1](https://www.makeriot2020.com/special-limited-offer-get-your-pcb-for-only-1/): A PCBPartner.com offer: 10 FR-4 PCBs (1-2 layers, up to 100x100 mm) delivered for $1, plus who PCBPartner are and why use them. (U57, 2022-04-14)
- [Easy to Use RA-02 Breakout Module](https://www.makeriot2020.com/easy-to-use-ra-02-breakout-module/): A better RA-02 LoRa breakout board: the problems with common breakouts, a design that fixes them, and use with Arduino, ESP32 and the Pico. (U56, 2022-04-09)
- [Easy to use CAN-BUS Module with Relay, LiPo Battery Backup](https://www.makeriot2020.com/can-relay-module-with-atmega8a-168-328/): An easy CAN bus relay module with ATmega MCU and LiPo battery backup, a remote node for the LoRa-CAN farm telemetry system. Schematic and PCB. (U55, 2022-03-22)
- [CAN-to-LoRa gateway using RA-02, MCP2515 and ATMEGA328P](https://www.makeriot2020.com/can-to-lora-gateway-using-ra-02-mcp2515-and-atmega328p/): A CAN-to-LoRa gateway with RA-02, MCP2515 and ATmega328P, linking wired CAN bus nodes to a long-range LoRa telemetry network. Design and PCB. (U54, 2022-03-19)
- [I2C IO Module with 4 Relay Outputs and 4 Galvanic Isolated Inputs](https://www.makeriot2020.com/i2c-io-module-with-4-relay-outputs-and-4-galvanic-isolated-inputs/): An I2C IO module with 4 relay outputs and 4 galvanically isolated inputs, to switch real-world loads safely from Arduino, ESP32 or ESP8266. (U53, 2022-03-14)
- [IO Shield for LoRa Base Module](https://www.makeriot2020.com/io-shield-for-lora-base-module/): An input and monitor shield for the LoRa base module: neat connections for infrared beam sensors and battery monitoring in a farm alarm system. (U52, 2022-03-13)
- [Sx127x-Ra-02-Test-Module with ATMEGA328P-AU](https://www.makeriot2020.com/sx127x-ra-02-test-module-with-atmega328p-au/): An SX127x (RA-02) LoRa radio board with ATmega328P-AU and LiPo backup, designed for farm security and real-time telemetry. PCB and design notes. (U51, 2022-03-10)
- [LoRa Base Module with ATMEGA328P](https://www.makeriot2020.com/lora-base-module-with-atmega328p/): A cheap, low-power LoRa base module with the Ai-Thinker RA-02 and an ATmega328P, built to test range for a farm monitoring project. (U50, 2022-02-25)
- [Build your own USB-ASP Programmer Clone](https://www.makeriot2020.com/build-your-own-usb-asp-programmer-clone/): Build a USBasp programmer clone to flash ATmega chips without an Arduino board: why, the circuit, the custom PCB and how to use it. (U49, 2022-02-21)
- [Automate your desk- or floor-standing fan](https://www.makeriot2020.com/automate-your-desk-or-floor-standing-fan/): Retrofit an ordinary oscillating desk or floor fan with an ESP8266 controller board for remote control and simple automation. Custom PCB included. (U48, 2022-02-17)
- [Remaking the STM32 Blue-Pill - Part 1](https://www.makeriot2020.com/remaking-the-stm32-blue-pill-part-1/): Redesigning the STM32 'Blue Pill' as a better board: what is wrong with the original layout and the goals for a new custom PCB. (U47, 2022-02-07)
- [Port Extender Card for the MCU-8266-12E](https://www.makeriot2020.com/port-extender-card-for-the-mcu-8266-12e/): Port extender card for the MCU-8266-12E IoT controller: more power outputs and easy I2C access, working with ESPHome and Home Assistant. PCB included. (U46, 2022-01-21)
- [Simplifying Robotics with Raspberry Pi® RP2040](https://www.makeriot2020.com/simplifying-robotics-with-raspberry-pi-rp2040/): Cytron Maker Pi RP2040: an RP2040 robot controller with dual DC motor driver, 4 servo ports and 7 Grove connectors, compared with the Maker Pi Pico. (U45, 2022-01-18)
- [ATMega328P prototype add-on card for use with the MCU-8266-12E IoT controller.](https://www.makeriot2020.com/atmega328p-prototype-add-on-card-for-use-with-the-mcu-8266-12e-iot-controller/): A custom ATmega328P add-on card for the MCU-8266-12E IoT controller, working as an Arduino Port Expander for ESPHome, with level conversion and PCB files. (U44, 2022-01-17)
- [Makrverse - A new platform for Makers](https://www.makeriot2020.com/makrverse-a-new-platform-for-makers/): Makrverse, a new platform connecting makers and tech enthusiasts with inventors, to get the latest gadgets straight from their creators. (U43, 2021-12-17)
- [Taking the next step with the IoT Controller.](https://www.makeriot2020.com/taking-the-next-step-with-the-iot-controller/): Next step for the ESP8266 IoT controller: an add-on shield for more sensors and a way to power the board straight from mains. (U42, 2021-09-02)
- [Design and build an ESP8266 IoT Controller, Part 3](https://www.makeriot2020.com/design-and-build-an-esp8266-iot-controller-part-3/): ESP8266 IoT controller part 3: the assembled PCB, three design mistakes and how they were fixed, and getting the board working. (U41, 2021-08-30)
- [Design and build an ESP8266 IoT Controller, Part 2](https://www.makeriot2020.com/design-and-build-an-esp8266-iot-controller-part-2/): ESP8266 IoT controller part 2: configuring ESPHome and Home Assistant for the board while the PCBs arrive from PCBWay. (U40, 2021-08-21)
- [Design and Build an ESP8266 Based IoT Controller - Part 1](https://www.makeriot2020.com/design-and-build-an-esp8266-based-iot-controller-part-1/): Design an ESP8266 (ESP-12E) IoT relay controller for Home Assistant and ESPHome: requirements, schematics, relay drivers, USB-serial and PCB layout. (U39, 2021-08-16)
- [Build your own 8 DI Optically Isolated Arduino Shield – Part 3](https://www.makeriot2020.com/build-your-own-8-di-optically-isolated-arduino-shield-part-3/): Assembly, testing and Arduino code for the 8 DI optically isolated I2C shield, with Gerber files to order your own board from PCBWay. (U38, 2021-07-30)
- [Build your own 8 DI Optically Isolated Arduino Shield – Part 2](https://www.makeriot2020.com/build-your-own-8-di-optically-isolated-arduino-shield-part-2/): The 8 DI optically isolated I2C Arduino shield in full: 3-32 V inputs, circuit diagram, typical wiring, the PCB layout and manufacturing. (U37, 2021-07-22)
- [Build your own 8 DI Optically Isolated Arduino Shield - Part 1](https://www.makeriot2020.com/build-your-own-8-di-optically-isolated-arduino-shield-part-1/): Why use opto-isolators to connect other voltages safely to an Arduino, and the optocoupler input circuit behind an 8-input I2C shield. (U36, 2021-07-21)
- [Free PCB Files available on Request](https://www.makeriot2020.com/free-pcb-files-available-on-request/): Three free PCB designs: an STM32 'Blue Pill' board in Arduino Uno size plus stackable, optically isolated 8 DI and 8 DO I2C shields. (U35, 2021-06-29)
- [Introducing Maker Pi RP2040](https://www.makeriot2020.com/introducing-maker-pi-rp2040/): Cytron's Maker Pi RP2040 robotics controller: RP2040 MCU, motor drivers, servo ports, Grove connectors and features, part 1 of a detailed look. (U34, 2021-06-06)
- [Your First Sketch - Embeetle IDE](https://www.makeriot2020.com/your-first-sketch-embeetle-ide/): Your first Arduino sketch in the Embeetle IDE: which project option to choose (not 'Create Empty'), and how the project files are laid out. (U33, 2021-05-29)
- [Arduino Support for the Pi Pico ...](https://www.makeriot2020.com/arduino-support-for-the-pi-pico/): Official Arduino IDE support for the Raspberry Pi Pico: add the board package and upload your first sketch, also on the Cytron Maker Pi Pico. (U32, 2021-05-28)
- [An Exiting new IDE for Micro Controllers](https://www.makeriot2020.com/an-exiting-new-ide-for-micro-controllers/): Meet the Embeetle IDE: a new, fast IDE for microcontrollers for makers who have outgrown the Arduino IDE, and first impressions of using it. (U31, 2021-04-05)
- [Maker Pi Pico with ESP01S Module](https://www.makeriot2020.com/maker-pi-pico-with-esp01s-module/): Give the Maker Pi Pico WiFi with the ESP01S (ESP8266) module through its socket: experiences, what worked and what did not. (U30, 2021-02-27)
- [Maker Pi Pico - Programming your board](https://www.makeriot2020.com/maker-pi-pico-programming-your-board/): How to put the Cytron Maker Pi Pico into upload mode and program its Raspberry Pi Pico, with first steps on the RP2040. (U29, 2021-02-08)
- [Introducing Maker PI Pico](https://www.makeriot2020.com/introducing-maker-pi-pico/): First look at Cytron's Maker Pi Pico: a maker-friendly carrier board for the Raspberry Pi Pico, packed with LEDs, buttons, buzzer, SD card and more. (U28, 2021-02-03)
- [Getting Started with the Raspberry Pi Pico -- Part 2 of the Pico Series...](https://www.makeriot2020.com/getting-started-with-the-raspberry-pi-pico-part-2-of-the-pico-series/): Getting started with the Raspberry Pi Pico: board specs, installing MicroPython by drag and drop, and using the MicroPython REPL. (U27, 2021-01-22)
- [Introducing the Raspberry Pi Pico](https://www.makeriot2020.com/introducing-the-raspberry-pi-pico/): First look at the Raspberry Pi Pico at launch: the RP2040 chip, its specifications, mechanical details and what makes this $4 board interesting. (U26, 2021-01-21)
- [Multiple LoRa Device Communication](https://www.makeriot2020.com/multiple-lora-device-communication/): LoRa part 3: code for the Heltec LoRa 32 V2 so several LoRa devices can talk to each other, with and without interrupts, ready for your own addressing. (U25, 2020-11-28)
- [LoRa - Part 2](https://www.makeriot2020.com/lora-part-2/): Which LoRa board to use: the Heltec LoRa 32 V2 (ESP32) reviewed, its specs, pinout and Arduino IDE setup, and a cheap module that is not worth buying. (U24, 2020-11-22)
- [What is LoRa?](https://www.makeriot2020.com/what-is-lora/): LoRa long-range radio for IoT: how it works, the Ai-Thinker Ra-02 (SX1278) module, wiring it to an Arduino and the software library to use. (U23, 2020-11-20)
- [MCP23017 with Adafruit Library](https://www.makeriot2020.com/mcp23017-with-adafruit-library/): Use the MCP23017 IO expander with Adafruit's library instead of the Wire library: pin numbering and simple Arduino examples. (U22, 2020-10-30)
- [A Business Card with a Purpose](https://www.makeriot2020.com/a-business-card-with-a-purpose/): A PCB business card with a working Arduino Nano-style circuit and micro-USB port built in, inspired by the JLCPCB user group. (U21, 2020-10-25)
- [ESP32/ESP8266 WiFi Config and OTA on Demand](https://www.makeriot2020.com/esp32-esp8266-wifi-config-and-ota-on-demand/): Let users set WiFi and options through a config portal, and update ESP32/ESP8266 firmware over the air on demand, for devices far away. (U20, 2020-10-17)
- [Using the MCP23017 to increase your GPIO's](https://www.makeriot2020.com/using-the-mcp23017-to-increase-your-gpios/): The MCP23017 16-bit I2C IO expander in depth: features, addressing, its registers (IODIR, GPPU and more) and Arduino code for extra GPIO pins. (U19, 2020-10-13)
- [Using I2C with a 4x4 Matrix Keypad](https://www.makeriot2020.com/using-i2c-with-a-4x4-matrix-keypad/): Connect a 4x4 matrix keypad over I2C with a PCF8574, saving 8 IO pins, plus Arduino code to read the keys on Arduino, ESP32 or ESP8266. (U18, 2020-10-05)
- [ESP8266 and ESP32 AT Commands](https://www.makeriot2020.com/esp8266-and-esp32-at-commands/): Reference of the most-used ESP8266 and ESP32 AT commands: basic, WiFi and TCP/IP, to use the module as a WiFi modem for another microcontroller. (U17, 2020-10-02)
- [SPI between Maker Nano ( Arduino Nano Clone ) and STM32 "Blue Pill" - Part 2](https://www.makeriot2020.com/spi-between-maker-nano-arduino-nano-clone-and-stm32-blue-pill-part-2/): Send data both ways over SPI between an STM32 'Blue Pill' and a Maker Nano (Arduino Nano clone), with wiring and code for master and slave. (U16, 2020-09-25)
- [What is SPI? Serial Peripheral Interface - Part 1](https://www.makeriot2020.com/what-is-spi-serial-peripheral-interface-part-1/): SPI explained: master and slave, MOSI, MISO, SCK and chip select, clock polarity and phase, the four SPI modes and how data is exchanged. (U15, 2020-09-18)
- [The OLED Display](https://www.makeriot2020.com/the-oled-display/): Add a small OLED display to your project: SSD1306 specs, wiring over I2C or SPI, the libraries to install and drawing text and graphics with Arduino. (U14, 2020-09-14)
- [Multiple I2C Devices on the same Bus, I2C Part 3](https://www.makeriot2020.com/multiple-i2c-devices-on-the-same-bus-i2c-part-3/): Run several I2C devices on one bus: a 16x2 LCD, a 128x32 SSD1306 OLED and two PCF8574 IO expanders, all from one Arduino Uno. (U13, 2020-09-12)
- [I2C between Maker Nano and Kid-Bright32 (Esp32)](https://www.makeriot2020.com/i2c-between-maker-nano-and-kid-bright32-esp32/): I2C between a Maker Nano (Arduino Nano clone) and a Kid Bright32 ESP32 board: master and slave code to share IO between the two. (U12, 2020-09-08)
- [What exactly is I2C?](https://www.makeriot2020.com/what-exactly-is-i2c/): I2C explained: the two-wire SDA/SCL bus, master and slave devices, addresses, start/stop, ACK/NACK, reading, writing and clock stretching. (U11, 2020-09-07)
- [Arduino Web Server - Part 2](https://www.makeriot2020.com/arduino-web-server-part-2/): Arduino web server part 2: serve the HTML page and images from an SD card to get around the Arduino's small memory, with full code. (U10, 2020-09-04)
- [Arduino Web Server using AJAX - Part 1](https://www.makeriot2020.com/arduino-web-server-using-ajax-part-1/): Make an Arduino web server that stays fast and responsive using AJAX and JavaScript on an Ethernet shield, to control IoT devices on your network. (U9, 2020-09-01)
- [ESP32 (Kid Bright v 1.3) Voice-Activated IoT Relay Control using IFTTT and Adafruit IO](https://www.makeriot2020.com/esp32-kid-bright-v-1-3-voice-activated-iot-relay-control-using-ifttt-and-adafruit-io/): Voice-controlled relays: an ESP32 Kid Bright board switched by Google Assistant through IFTTT and Adafruit IO, with code and a video. (U8, 2020-08-30)
- [A glance back in History - Manufacturing your own transistors - At home!](https://www.makeriot2020.com/a-glance-back-in-history-manufacturing-your-own-transistors-at-home/): Electronics history: chapter 1 of the 1954 book 'Practical Transistors and Transistor Circuits', on making your own transistors at home (free PDF). (U7, 2020-08-28)
- [Extending Arduino/Esp32/STM32 GPIO Pins - PART 2](https://www.makeriot2020.com/extending-arduino-esp32-stm32-gpio-pins-part-2/): Add GPIO pins over I2C with the PCF8574 IO expander: wiring, addressing and Arduino code for extra inputs and outputs on Arduino, ESP32 or STM32. (U6, 2020-08-28)
- [Extending the Inputs and Outputs of your Arduino/ESP32/STM32](https://www.makeriot2020.com/extending-the-inputs-and-outputs-of-your-arduino-esp32-stm32/): Run out of pins? Shift registers explained (SISO, SIPO, PISO) and how to add outputs to Arduino, ESP32 or STM32 with a 74HC595. (U5, 2020-08-21)
- [Useful Circuits using NAND Gates - Logic Gates Part 2](https://www.makeriot2020.com/useful-circuits-using-nand-gates-logic-gates-part-2/): Two useful NAND-gate circuits with the CD4011: a capacitive touch on/off switch driving a relay, plus schematics and how they work. (U4, 2020-08-14)
- [Using MQTT with IoT Devices - A Short Summary](https://www.makeriot2020.com/using-mqtt-with-iot-devices-a-short-summary/): What MQTT is and how it works: brokers, topics, publish and subscribe, and how to use it with Arduino, ESP32, STM32 and your smartphone. (U3, 2020-08-14)
- [Previous Posts](https://www.makeriot2020.com/previous-posts/): Links to older MakerIoT2020 posts: Arduino with LCD and HC-SR04, nRF24L01 remote IO, STM32 Blue Pill, H-bridge motor control and logic gates. (U2, 2020-08-14)
- [Welcome to our New Site](https://www.makeriot2020.com/welcome-to-our-new-site/): MakerIoT2020 moves to its own domain: a short note on the new site, doing it all yourself, and where the older posts stay available. (U1, 2020-08-13)

## Pages

- [Contact Us](https://www.makeriot2020.com/contact-us/): How to reach MakerIoT2020: an online-only maker business in Thailand. Contact via Facebook Messenger or Patreon, with business hours in GMT+7.
- [Make your own](https://www.makeriot2020.com/make-your-own/): Build it yourself: free custom PCB designs, motor control, logic building blocks, I2C, SPI and ESP8266/ESP32 projects you can make at home.
- [What is an H-Bridge Motor Controller](https://www.makeriot2020.com/make-your-own/what-is-an-h-bridge-motor-controller/): How an H-bridge works: the circuit that reverses current through a DC motor or stepper coil, explained step by step for beginners.
- [Using the H-Bridge Motor Controller - A Practical Example](https://www.makeriot2020.com/make-your-own/using-the-h-bridge-motor-controller-a-practical-example/): Build an H-bridge from discrete parts to drive big DC motors (like old drill motors), with Arduino sample code for direction and PWM speed control.
- [PCB Files for Dual H-Bridge](https://www.makeriot2020.com/make-your-own/pcb-files-for-dual-h-bridge/): Free Gerber files for a dual H-bridge PCB that drives two DC motors or one bipolar stepper, plus how to order the board from a PCB maker.
- [Logic Building Blocks - The Logic Gates](https://www.makeriot2020.com/make-your-own/logic-building-blocks-the-logic-gates/): Build AND, OR, NOT, NAND and NOR logic gates from transistors and resistors, useful when DIP logic chips are hard to find.
- [Easy Arduino Tutorials](https://www.makeriot2020.com/arduino-tutorials/): Index of easy Arduino tutorials: extending inputs and outputs, Arduino web servers with AJAX, I2C devices and SPI with the Arduino Nano.
- [STM32 Projects](https://www.makeriot2020.com/stm32-projects/): STM32 'Blue Pill' hub: pin diagram, programming with the Arduino IDE, enabling the native USB port, SPI with Maker Nano and free PCB files.
- [Programming the "Blue Pill" with Arduino IDE](https://www.makeriot2020.com/stm32-projects/programming-the-blue-pill-with-arduino-ide/): Program the STM32F103C8T6 'Blue Pill' from the Arduino IDE through a USB-to-UART adapter, and why the wrong USB resistor blocks native USB uploads.
- [Using the Native USB port on your "Blue Pill"](https://www.makeriot2020.com/stm32-projects/using-the-native-usb-port-on-your-blue-pill/): Advanced: fix the USB D+ resistor and flash a bootloader so the STM32 'Blue Pill' uploads Arduino sketches over its own USB port.
- [Using The Embeetle IDE](https://www.makeriot2020.com/using-the-embeetle-ide/): Articles on the Embeetle IDE: a light, fast embedded IDE for makers, with a first-project walkthrough and an introduction to its features.
- [Home Automation](https://www.makeriot2020.com/home-automation/): DIY home automation projects: why build your own instead of buying cloud gadgets, with links to ESP32, ESP8266 and Home Assistant builds.
- [Privacy Policy for Maker and IoT Ideas](https://www.makeriot2020.com/privacy-policy-for-maker-and-iot-ideas/): Privacy policy of MakerIoT2020 (Maker and IoT Ideas): what information is collected, how it is used, log files, cookies and Google advertising.
- [Custom PCB Service](https://www.makeriot2020.com/custom-pcb-service/): Open-source custom PCB designs from MakerIoT2020: tested, working boards to order and assemble yourself, or buy assembled, with example firmware.
- [Quality Prototyping Modules](https://www.makeriot2020.com/quality-prototyping-modules/): Prototyping boards worth using: what makes a good module, and the Cytron Maker Nano, Maker Uno, Maker Nano RP2040 and Maker Pi RP2040.

## Optional

- [All projects](https://www.makeriot2020.com/projects/): full list, 20 per page
- [Sitemap](https://www.makeriot2020.com/sitemap.xml)
- [RSS feed](https://www.makeriot2020.com/feed/): newest 20 posts