Introduction

The VS1053b is an audio codec chip that supports a wide variety of formats, including Ogg Vorbis, MP3, AAC, WMA, FLAC, and MIDI. For applications in electronic musical instruments, its Real-Time MIDI mode is particularly useful. Simply by sending MIDI commands to the chip via UART, you can play the sounds of various musical instruments.

Real-Time MIDI mode

To use Real-Time MIDI mode, you need to ensure that GPIO0 is low and GPIO1 is high when the chip is powered on; after that, it's ready for use.

No additional commands or control from an external MCU are necessary. It's very simple.

GPIO0 is configured as a pull-down, and GPIO1 is configured as a pull-up.

All that's left to do is send MIDI commands to the VS1053b, and the sound will be played.

MIDI IN

The MIDI signal is processed by a standard MIDI input circuit, where the signal from the MIDI connector is isolated using a photo-coupler and then connected to the UART RX pin of the VS1053b chip.

PCB

Thanks to the PCBWay, I was able to produce high-quality circuit boards quickly this time.

The circuit board arrived in Japan about a week after I placed the order.

The delivery time was short, and the matte black solder resist we specified turned out beautifully.

I was satisfied with the quality.

After I received the PCB, I manually soldered the components onto the PCB.

DEMO VIDEO

Please watch this demo video which shows various instrument sounds from the VS1053b chip being played via MIDI.