I recently received my Yaesu FTM-400DE (European version, American is FTM-400DR) and would love to try to assist in adding support for it in Chirp.
The one I ordered has unlocked TX frequencies, so if someone else has one without that we may be able to find out where that setting is.
This tranceiver comes with a data cable, but I have no software to talk to it regarding settings. It can also save settings to a microSD card, and the only programming software for it that I have found uses this method (only, no support for cable).
I have cloned the development tree and try to find how the FTM-350 module works regarding memory download to see if can start there. I can also start analyzing the memory image saved to µSD, but it will be a bit tedious to change one setting, turn the thing off, take the µSD card to the computer, copy the settings file, compare it to the previous version, put the card back, turn on the radio, change another setting, and so on. :-)
Johan Adler Stockholm, Sweden