Engineering Library
Curated hardware pinouts, open-source firmware drivers, schematics, mechanical CAD standards, and rapid cheat sheets for makers and engineers.
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ESP32-S3 Dual-Core SoC Complete Pinout & GPIO Matrix
Full hardware pinout mapping of GPIOs, ADC1/ADC2 channels, Strapping Pins, JTAG, and USB-OTG.
Source: EI House Hardware Lab & Espressif
STM32F401 BlackPill Hardware Schematic & Bootloader Reference
Full open-source circuit diagram, power regulation, crystal oscillator circuit, and DFU bootloader jumpers.
Source: STMicroelectronics & WeAct Studio
Standard E12, E24, E96 Resistor & Capacitor Decade Values
Complete nominal value chart for standard 5% (E24) and 1% (E96) tolerance passive components.
Source: EI House Technical Publishing
I2C vs SPI vs UART Protocol Specifications & Pull-Up Guidelines
Bus speed limits, maximum wire capacitance, pull-up resistor sizing formulas, and multi-slave topologies.
Source: EI House Embedded Engineering Group
Metric Fastener Standards & Tap Drill Hole Clearance Chart
Standard drill sizes for M2, M2.5, M3, M4, M5, M6 internal threads and clearance hole dimensions.
Source: ISO Standards & EI House Workshop
NEMA 17 & NEMA 23 Stepper Motor Dimensional & Faceplate Standards
Faceplate mounting hole centers, pilot boss diameter, D-shaft flats, and wiring phase color codes.
Source: National Electrical Manufacturers Association
2020 & 2040 Aluminum V-Slot & T-Slot Extrusion System Reference
Cross-sectional profiles, moments of inertia, compatible drop-in T-nuts, and corner bracket sizing.
Source: OpenBuilds & EI House Prototyping
Embedded Linux & Raspberry Pi Terminal Commands Quick Guide
Essential commands for device tree inspection, GPIO export, systemd service management, and network diagnostics.
Source: EI House Software Team
FreeRTOS API Quick Reference & Kernel Architecture Blueprint
Task creation, mutexes, binary/counting semaphores, queue management, software timers, and ISR safe functions.
Source: AWS FreeRTOS & EI House Firmware Lab
MQTT v3.1.1 / v5.0 Protocol Specification & Topic Design Best Practices
QoS 0/1/2 delivery semantics, keep-alive heartbeats, last will and testament (LWT), and multi-tenant topic hierarchies.
Source: OASIS Standard & EI House IoT Group
FDM 3D Printing Defect Diagnostic & Troubleshooting Matrix
Visual diagnostic chart resolving stringing, layer shifting, elephant foot, under-extrusion, warping, and z-banding.
Source: EI House Rapid Prototyping Workshop
Engineering Clearances & Tolerances for 3D Printed Assemblies
Clearance guidelines for press fits, sliding joints, snap fits, and captive nut recesses.
Source: EI House Mechanical Design Lab