PreenFM Forum

PreenFM => preenfm2 and preenfm3 => Topic started by: Xavier on January 01, 2014, 03:50:24 PM

Title: FAQ
Post by: Xavier on January 01, 2014, 03:50:24 PM

Where can i find FM documentation ?

Forum member "fori" recently post this list

Where are the last firmwares or other files to download

preenfm2 : (
preenfm3 : (

The encoders does not respond correctly

If you need 2 ticks to increase by one the value or if one tick increases by 2 the values, you need to change the encoder drivers.
In the menu (Menu > tools > set > "Rot. enc.") you can chose between 2 encoder drivers: 12 and 24.

How do i enter the bootloader

Press any key when turning on the preenfm2.
Press the menu key when turning on the preenfm3.


SD card Error #-6# with the preenfm3

See this thread (


My display remains black when i turn on the preenfm2

Check that you removed the jumper JMP3, and turn it off and on again.

The Midi over USB does not work / The Led is not flashing on midi clock beat

Must be enable in the settings.

Can i access USB drive without opening my PreenFM2

Yes you need bootloader 1.10+
The PreenFM2 registers to your computer as a mass storage and redirect all low level access to the USB stick.
Don't expect high bandwidth, but it works :-)

What are P1, P2 and P3 for ?

. P1 allows you to plug a st-link v2 debugger.
. P2 extension port  (removed from PCB R5)
. P3 analog input. CV you need the adcIn branch of the github repository :

Except P1, none of them is useful today, and i cannot guarantee they will be useful someday.

TroubleShooting / It does not work

You can start by reading this thread :
And verify the different points shown of message #6.