Interface between the BBC micro:bit and the Grove MP3 v2.0.
The above image shows the plug-and-play setup with the micro:bit connected to the Grove MP3 v2.0 via the Grove shield for micro:bit. With basic tools, it would also be possible to connect the Grove MP3 v2.0 to the micro:bit using three alligator clips.
The hello-mp3.js program provides the minimal functionality for testing the interface between the micro:bit and the Grove MP3 v2.0.
The hello-mp3.js program is configured to expect:
- micro:bit P14 connected to the RX of the Grove MP3 v2.0
- a file called 001xxx.mp3 (xxx can be the filename, for example) within a folder called 01 on the SD card
On startup, the hello-mp3.js program will select the SD card as a source, set the volume to 24 / 30 and display the 'play' icon on the LEDs.
Pressing button A will begin (or restart) playback of the 001xxx.mp3 file within the 01 folder.
Seeed provide a version of the KT403A datasheet, which specifies the serial commands interpreted by the Grove MP3 v2.0 module. In short, all communication is in 8-byte messages at 9600 baud. The message structure is as follows:
| Byte | Value | Function |
|---|---|---|
| 0 | 0x7e | Start command |
| 1 | 0xff | Version info |
| 2 | 0x06 | Message length |
| 3 | Command (see datasheet for list of commands) | |
| 4 | 0x00 | No serial reply requested |
| 5 | High byte of command data (DH) | |
| 6 | Low byte of command data (DL) | |
| 7 | 0xef | End command |
MIT License
Copyright (c) 2018 GenieMob
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