Frequently Asked Questions - uMP3

uMP3 Playback Module

You will need to have a USB/RS232 to TTL Serial adapter to connect between your PC and the uMMC/uMP3/rMP3.

(You can use an Arduino or Arduino-clone to connect to the uMMC/uMP3/rMP3 using a serial pass-through application - see this)

Make sure the connection is such that the "T" connection on the uMMC/uMP3/rMP3 connects to the "input" to the Host/PC and the "R" connection goes to the "output" from the Host/PC.

Start a "Command Prompt" on the PC and navigate to where you have extracted the firmware files for the uMMC/uMP3/rMP3.

From there, you can execute:

update firmware.rfw -COM1

(replace "firmware.rfw" with the file included in the ZIP)

and the update program will update the firmware on the uMMC/uMP3/rMP3. NOTE: you can change the -COM1 to whatever serial port you are using.

A progress will show the status of the update, and once it reaches 100%, the update will be complete. The uMMC/uMP3/rMP3 will automatically restart after the update.

(We are working on a java version of an uploader. If you would like to help, please contact

The uMP3 Playback Module is 2.5 inches by 2 inches (6.35cm by 5.08cm).

Yes. You can find the chipset pricing for the uMMC/uMP3 on the product information page. You can also find information on integrating the chipset under the download section of the product information page.

The uMMC/uMP3 hardware uses a LDO (Low Drop-Out) voltage regulator. You can use 3.0V or 3.3V as the input voltage, but you need to ensure that the serial lines do not exceed the supply voltage (3.0V or 3.3V respectively).

EF2 happens when the file in the path does not exist.
e.g. Opening a file for reading that does not exist.

EF5 is essentially the same as EF2, but something in the middle of the path does not exist.
e.g. /DIR1/BADDIR/LOG/FILE.TXT - where BADDIR does not exist.

EE7 occurs when you open a file, but the path specifies a directory.

The life span for a uMMC/uMP3 unit is only limited by the contact wear on the MMC card connector - which is rated at up to 12,000 plug-in cycles.