# ESP-BIST in Action: A Self-Testing HMI using ESP32-P4

DevFeed: [ESP-BIST in Action: A Self-Testing HMI using ESP32-P4](<https://devfeed.tech/articles/esp-bist-in-action-a-self-testing-hmi-using-esp32-p4-13787.md>)

Original publisher: [Read original article](<https://developer.espressif.com/blog/2026/08/esp-bist-motor-controller-hmi/>)

Author: John Lee

Published: 2026-08-22T00:00:00Z

Content type: tutorial

Language: en

Sources: [Blog on Developer Portal](<https://devfeed.tech/sources/blog-on-developer-portal.md>)

Topics: [ESP32-P4](<https://devfeed.tech/topics/esp32-p4.md>), [Testing](<https://devfeed.tech/topics/testing.md>), [Test coverage](<https://devfeed.tech/topics/coverage.md>), [Espressif](<https://devfeed.tech/topics/espressif.md>), [Microcontroller](<https://devfeed.tech/topics/microcontroller.md>), [RISC-V](<https://devfeed.tech/topics/riscv.md>), [boot](<https://devfeed.tech/topics/boot.md>)

Tags: [blog](<https://devfeed.tech/tags/blog.md>), [display](<https://devfeed.tech/tags/display.md>), [esp32-p4](<https://devfeed.tech/tags/esp32-p4.md>), [espressif](<https://devfeed.tech/tags/espressif.md>), [hmi](<https://devfeed.tech/tags/hmi.md>), [lvgl](<https://devfeed.tech/tags/lvgl.md>), [modbus](<https://devfeed.tech/tags/modbus.md>), [risc-v](<https://devfeed.tech/tags/risc-v.md>), [safety](<https://devfeed.tech/tags/safety.md>), [startup](<https://devfeed.tech/tags/startup.md>), [test-coverage](<https://devfeed.tech/tags/test-coverage.md>), [testing](<https://devfeed.tech/tags/testing.md>)

## AI overview

This tutorial explains how ESP-BIST provides IEC 60730 Class B self-test coverage on Espressif SoCs. It demonstrates an ESP32-P4-powered HMI using an M5Stack Tab5, Modbus communication with a simulated motor controller, and an LVGL touchscreen. The article describes post-boot and runtime tests, safe-state handling, and Host Diagnostics using the low-power RISC-V core.

## Source excerpt

ESP-BIST brings IEC 60730 Class B self-test coverage to Espressif SoCs, and this article walks through what that actually means before putting it to work. Using an ESP32-P4-based M5Stack Tab5 as a Modbus HMI for a simulated motor controller, we show how a SoC that can prove its own health is a chip you can trust to draw a "safe" screen without lying about it.