I would like to add some info, as I’ve gotten ‘thefreeman’s’ adapter (I don’t have GChart’s though).
The “additional signaling pad” which you mentioned has been useful, since I connected a dupont wire to them to flash a TS30S Pro (the TS30S Pro also uses the same ATTiny1616, but the pins are spaced farther apart than the ones on the TS10, TS11, TS25, FC13 or LT1S Pro.)
I connected another dupont cable extension to flash a Q8 Plus (which also features the same 3 pins (farther spacing) as the TS30S Pro, but 2 pins are swapped) – since I didn’t quite understand what the “V G D” (TS30S Pro) and “G V R” (Q8 Plus) meant, it was sort of through testing that I find to swap the position of 2 wires, and then I was also able to flash the Q8 Plus successfully. ( I used “Read” mode while I was testing which pin is correct for the Q8 Plus)
(
“R - +” corresponds to “D G V” on the TS30S Pro
“R + -” corresponds to “R V G” on the Q8 Plus
)
(re: using USB-A-to-C and USB-C-to-C cable on thefreeman’s adapter:
while connecting to my desktop PC (Windows), I used a USB-A-to-C cable
while connecting to my Android phone, I used a USB-C-to-C cable
both worked flawlessly)