Programmable Music Module

Simtelic Music Module is a user-programmable module that uses RTTTL data to store and play melodies.

EL0003 - Programmable music module.

RTTTL, which stands for Ring Tone Text Transfer Language, was created to provide a simple, text-based format for sharing ringtones on early mobile phones. Developed by Nokia, it quickly became popular due to its compact size and compatibility with text messaging services. This format allowed users to easily exchange custom melodies without needing specialized software or data connections.

RTTTL is a human-readable data format where each ringtone is represented as a sequence of notes, durations, and optional settings.

According to Simtelic naming conventions, this module is identified as EL0003 and is available for purchase online.

Top view of the EL0003 module.

This module is built around a 32-bit MCU, a 2Kbit EEPROM, and a CH340 USB bus conversion chip. It is compatible with the latest Windows and Linux-based PCs. The module is user-friendly and provides capabilities similar to the older UM series musical chips. Its main objective is to serve as a replacement for popular melody generator chips such as the UM66, UM3561, UM3481, and others.

This module is powered by the USB bus and provides an analog AF output. It is capable of driving a small 8Ω speaker. The module features a jumper to select between different playback modes. When the jumper is open, it plays a programmed melody on a continuous loop. When the jumper is closed, the melody plays only once. To play the melody again, the user must press the push button on the module.

To flash the module, use the RTTTL loader script available in the Simtelic GitHub repository. This Python script connects to the module and transfers the specified RTTTL data file into it. The programming process takes less than 20 seconds and automatically resets the module after the flashing operation is complete. With this script, users can upload RTTTL data into the module, which can be up to 256 characters long.

To use the loader script in a Linux environment, follow the steps outlined below:

1. Get loader script from Simtelic GitHub repository:

git clone https://github.com/simtelic/el0003-music-module.git

2. Install pyserial:

pip install pyserial

Use a tool like ls /dev/tty* or dmesg | grep tty to find the serial port assigned to your music module. It's typically named /dev/ttyUSB0, but it might vary.

3. Run the loader script:

python3 rttl-loader.py -p ttyUSB0 -m write -f sample.txt

RTTTL models can easily be found on the web. A few notable repositories are FlipperMusicRTTTL and the RTTTL player. Note that all RTTTL scripts provided on these sites do not work with this module, as it can only accommodate melodies that are up to 256 characters long.

This module has certain limitations. It primarily supports monophonic melodies and provides limited control over complex musical elements such as rests, ties, or dynamic changes. These limitations are inherent to RTTTL.

The module datasheet is available on the Simtelic product page.

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