Reading 2nd and 3rd mouse/pad buttons

[Keir]

I just had a bug report on Amiga Test Kit (https://github.com/keirf/Amiga-Stuff/issues/19) that middle mouse button is not working with a TOM+ adapter and one specific A1200 board:
1. Same TOM+ works with Test Kit on another A1200 board
2. TOM+ works with the bad board on WB and WHDLoad, apparently
3. TOM+ pin 5 doesn't work with TestKit on bad board in port1 or port2.

Now, my button handling is not really very complicated, but I do want to confirm I'm setting POTGO correctly. My understanding is that it is correct to set the appropriate nibble (for port 1 or port 2) to %1111, so that the pins are in "output mode" and pulled high. So that's what I do: I set POTGO to $FF00 during the mouse test (https://github.com/keirf/Amiga-Stuff...kit/joymouse.c).

This seems to agree with other information I've found, and also with a quick peek at Kickstart code and its execution. I would probably have left it there except I found one dissenting fragment in the WHDLoad history (http://www.whdload.de/docs/History.html):
"fix: potgo set to input mode now, fixes right mouse button problem with ArcherMcLeanPool and JimmyWhiteSnooker (Mr.Larmer)"

So I decided to ask here. Does anyone have any idea on what's going on here, and whether my POTGO setting is best practice?