u/Hot_Performance8013

I had a KB2040 that was bundled in with a purchase and thought I put it to good use by using the built in i2C hardware logic block with-in the RP2040. Defined a packet payload so that I can send and fetch serial data over USB to communicate with i2c peripherals.

Code concept should be adaptable to any MCU and should facilitate hardware debugging/tuning while saving time when utilizing a graphical interface.

UF2, INO files available via GitHub (KB2040-I2C-Bridge)

Hi everyone,

I’ve been experimenting with a diagnostic architecture designed to eliminate the need for writing throwaway desktop scripts (like custom Python or serial CLI tools) during early-stage silicon evaluation and board bring-up.

Instead of rolling a custom local UI or managing script dependencies just to read and write specific register addresses, the approach uses WebSerial to map browser-based graphical components directly to register control-plane logic.

The architecture relies on a basic microsecond passthrough bridge. A standard microcontroller is flashed with a basic bridge script to map incoming serial byte arrays from the browser context directly onto physical I2C or SPI bus lines.

The Test Architecture:
To evaluate the protocol latency and stability, I set up a basic dual-core ARM Cortex-M0+ board running a transparent C++ USB-to-I2C bridge firmware. This allows real-time interactive read/writes to hit an I2C pressure sensor register map via the browser environment.

The underlying framework decouples the graphical interface entirely from the host operating system and physical debugger hardware.

Core Firmware Workflow Benefits:

• Hardware Abstraction: The graphical layout maps to the register definition, not the host code—meaning you can swap the bridge MCU or interface hardware without rebuilding a testing panel.
• Zero Host Dependencies: Because the application executes strictly within a standard browser tab via native WebSerial APIs, there is no toolchain installation required across different engineering workstations.
• Rapid Bitwise Diagnostics: Useful for manually injecting error states, checking interrupt flags, or sweeping configuration registers before committing final hardcoded logic to a production firmware image.

I'm curious how others on the bench approach early-stage register verification. Do you find yourself relying primarily on vendor GUI tools, custom terminal scripts, or has anyone explored similar browser-serial abstractions for prototyping panels?