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wCoreF4

Introduction

This is a cross-grade of the STM32F4 Core based on the Core407v breakout board from Waveshare. There are other versions of MCU breakouts, but the Waveshare one seems quite a reputable source with decent distribution and documentation.

Pros

  • Slightly smaller footprint
  • (Almost) all connectors on same face
  • Proper USB A and B ports
  • Footswitch/gate 3.5mm jack
  • Hardware host/slave switch
  • LEDs on the panel
  • Reset button on the panel
  • User button on header
  • More mounting options available (e.g. panel mount including USB)
  • 1A 3v3 regulator
  • Possibility for external Vref (for AIN)

Cons

  • Similar height to Disco version (could cut off headers etc.)
  • Lacks ST-LINK and requires a (cheap) programmer or a Discovery module
  • No mounting holes on MCU breakout
  • Requires SMT soldering (wide pitch)

Sub parts

The Core is split over three PCBs:

The MIDI interfaces were also redesigned:

Build instructions are found on the appropriate pages.

MCU module

The actual MCU module is available from several sources:

Burning the bootloader

The MCU module has a USB port, but direct programming would only be possible with a USB-UART programmer. It would also require a different bootloader protocol. Instead, we make use of SWD functionality. The MCU module has a typical JTAG/SWD header and these pins are also available on the two 2*25 header rows.

These are readily available from eBay and other sellers for typically <$10. You only require one programmer to flash as many modules as needed.

Option 2: use a Discovery module

The Discovery module (even if connected to a MIDIbox Core) can be used for programming. To do so, remove the two CN3 jumpers labelled ST-LINK/DISCOVERY. This disconnects the SWD interface from the STM32F4 MCU on the Discovery board:

Flashing over SWD

The following five connections should be made with DuPont cables:

  • 3v3
  • 0V/ground
  • DIO
  • CLK
  • RESET

After that, follow the instructions for the initial flash of a Discovery module.

If the JTAG/SWD header of the 407v board had to be removed and the MCU required re-flashing, it's possible to do so using the named pins on the 2*25 header.


License

Currently the design is © 2017 antilog devices with all rights reserved; all documentation is CC BY-NC-SA 3.0.

wcore.1505071218.txt.gz · Last modified: 2017/09/10 19:20 by latigid_on