Programming the ESP32 with an ARM Cortex-M USB CDC Gateway

The Espressif ESP32 devices are getting everywhere: they are inexpensive, readily available and Espressif IDF environment and build system actually is pretty good and working well for me including Eclipse (see “Building and Flashing ESP32 Applications with Eclipse“). The default way to program an ESP32 is to a) enter UART bootloader by pressing some push buttons and b) flash the application with ESP-IDF using a USB cable.

That works fine if the ESP32 is directly connected to the host PC. But in my case it is is behind an NXP Kinetis K22FX512 ARM Cortex-M4F microcontroller and not directly accessible by the host PC. So I had to find a way how to allow boot loading the ESP32 through the ARM Cortex-M which is the topic of this article.

TTGO ESP32 MICRO-D4 Module

TTGO ESP32 MICRO-D4 Module

Continue reading

Advertisements

DIY USB HID Joystick Device and Game Controller

For many projects it would be cool to build a custom USB Joystick device, either as custom game controller for Windows or any USB host which can be used with a USB Joystick. Instead buying one, why not build my version? All what I need is a USB capable board, some kind of input (potentiometer, push buttons) and some software, and I have my USB Joystick:

DIY USB HID Joystick Device

DIY USB HID Joystick Device

Continue reading

Enclosure for the Remote Robot Controller with LCD Display

The first enclosure for the INTRO robot remote controller board (see “INTRO Robot Remote – First Production PCB“) is ready, and it is looking good:

Enclosure for the Remote Controller Board

Enclosure for the Remote Controller Board

Continue reading

USB with the TWR-KL25Z48M Board: Check Jumper J18!

When I ordered my first Freedom FRDM-KL25Z board, I placed an order the Tower TWR-KL25Z48M shortly afterwards. But I was so happy with the FRDM-KL25Z, and because the FRDM board is much less expensive and easier to handle, that Tower board was sitting in my board shelf, waiting for a maybe a student project or to get any other use of it. Well, I can tell that my students wanted the FRDM board, not the Tower board ;-). But when I saw this week in the Freescale forum a user asking for a USB example for that Tower board, I thought that now I could at least use that board to help someone out.

MKL25Z128VLK4 on the TWR-KL25Z Board

MKL25Z128VLK4 on the TWR-KL25Z48M Board

Continue reading

Getting Bluetooth Working with JY-MCU BT_BOARD V1.06

For my embedded course at the University of Lucerne of Applied Sciences and Arts I needed more Bluetooth modules for the Zumo/Sumo robots. I run out of stock as the modules are getting popular and are used in many student projects. So I ordered a handful more from DX/DealExtreme of the same HC-06 type/part number I already ordered a while back. I expected that they will work as the modules I had ordered from DX half a year ago. Was that naïve? Probably. Because they did *not* work, and caused me to reverse engineer the modules and to apply a hardware fix to get them working….

Set of JY-MCU Bluetooth Modules

Set of JY-MCU Bluetooth Modules

 

Continue reading