What is SpaceFN and why you should give it a try
The SpaceFN concept - setting up your space key as a layer switch when held - is probably one of the most useful tweaks in the keyboard hobby. Let me explain how it works. My SpaceFN article on kbd.news made some rounds recently - quite surprisingly given the age of this concept. This piece you're reading is a condensed version of the full post. If you're left with unanswered questions, you'll most likely find the info you're looking for in the original write-up. On my imaginary top list of the most useful keyboard features, tweaks and hacks, SpaceFN would deserve a podium finish for sure. But what makes it so special? In short: SpaceFN is easy to implement, easy to learn, costs nothing, can be used with any keyboard, and can improve your productivity instantly. I will list its benefits below, but can state right at this point that the SpaceFN concept, setting up your space key as a layer switch when held, is clearly one of the most useful tweaks in the keyboard hobby....
Apr 30, 2024
https://www.dropbox.com/s/in3ny6p2b8trbj4/2015-12-23%2001.50.16.jpg?dl=0
PS: 4mm clearance is enough for routing some extra cables - and for carefully picked resistors.
You're now implying its TQFP, right?
Pins are "tiny" but it is possible (flux bathing in advance works wonders). E2 pin (have not gone properly through firmware, but it looks unused on MiniVan) is a usual suspect, when adding things on 32u4 boards, because is considered more accessible due to being exposed on the corner (see: github.com/jackhumbert/qmk_firmware/blob/master/keyboards/satan/controller.jpg ). Adjacent C6, C7 look unused as well. B2 and B1 far away onto other corner (B3 is used, B7 is probably used as backlight).
EDIT:
Did found some pictures Evan made public some time ago for R1 ( https://geekhack.org/index.php?topic=80988.msg2176821#msg2176821 ).
Package looks like it is QFN and can't tell orientation (by crystal location, I would guess E2 is horizontal pin on upper right corner). It's hard to solder in there. All solutions, I can think of, require either some serious skill, or equipment, or both.