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.
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:
Time is passing fast, and many components have been updated to make the compatible with the NXP Kinetis SDK V2.0. As a highlight, besides of FreeRTOS the following components are now usable with the NXP Kinetis SDK:
It has been already two months after the Feb 2016 release, and so much things are going on, so a new release was overdue. Today I have released a new version of the McuOnEclipse components on SourceForge with the following main changes and features:
Kinetis SDK v2 with Processor Expert: Now many components can be used even with the Kinetis SDK v2.0 even with the Kinetis SDK not having Processor Expert included.
Updated Segger SystemViewer to v2.32a with post-mortem and static buffer support
Updated Segger RTT to v5.10u and fixed an issue with interrupts on Cortex-M4
These days machines do not have physical serial (COM) ports any more. I do not understand why the USB group had missed to define a clean serial communication standard :-(. And the same mistake gets repeated for BLE again 😦 :-(. So every vendor and provider has its own USB CDC driver and interface. And it is really a big pain of the virtual COM/USB CDC ports installed. I have seen countless cases where “the USB UART or CDC port does not work”. So if you have such a problem, I might have a tip for you: Show hidden devices in the Windows Device manager. But in a special way I had not thought about it!
The FRDM-K22F is one of the latest members of the Freedom board families: 512 KByte Flash, 128 KB RAM and the usual Freedom board components on it. Unfortunately, Freescale decided not to populate the micro-SD card connector on the board, so from this perspective the FRDM-K64F is more value for the money. But the board has USB, so this makes it still interesting. And this is what this post is about: Adding USB to the FRDM-K22F board in a few minutes…
Travel is a hassle these days: airline on strike in Europe, long security lines at the airport, bumpy flight and long transfer to the hotel which is so tiny that the taxi driver missed it twice! Anyway, at least this time the reservation of the room *did* work. Arrived completely tired and with notebook batteries drained and empty. Unpacked the power adapter, ready to charge it up. Only to realize that the notebook power supply cable does not match the travel adapter plug! :-(:
Travel Power Adapter Mismatch
So I have packed the 3-pin notebook power supply instead my usual travel 2-pin one 😦
I have received several requests to post a quick note when there is a new release (16-Nov-2014) of the McuOnEclipse components on SourceForge (see “McuOnEclipse Releases on SourceForge“). I have published today a new release, and with following major improvements:
USB support for Kinetis KL24Z
FatFs now features the latest Elm-Chan v0.10c release
Backspace support in Shell
Configuration item in FreeRTOS for Percepio Trace Hooks
Sometimes I think that a problem should be solvable in a few minutes, and then it turns out that it lingers around for months. Very, very frustrating! Such a thing is getting the USB 4.1.1 stack running on the FRDM-K64F board. I have that board since April 2014, and it took me 7 months to get the FSL USB stack running on it :-(.
Sometimes I have a good idea how to extend one of my Processor Expert components with an extra feature, but then I step back because why implementing more than I need at the moment? Until another user of the component simply asks for the same thing, and here we go: if one or more can take advantage of a feature, that’s definitely a strong argument to add it :-). This happened with the RingBuffer Processor Expert component I’m using in many projects. And a reader of this blog asked to add some extra event methods: when an item is added or removed to the buffer.
RingBuffer used in USB Component with Extra Events