ah, thx for the clarifcation
then two test points/solder pads for serial5 would do it
ideally, CAN would get its own plug, and serial4 gets these pins, but that's probably not easily possible without major redesign
I myself would not mind if e.g. S7 and S8 would go to one of the 3-pin rows (i.e. no extra +VS for S7 and S8), serial 5 could then go to there (no +5V for serial5, but so what), and serial4 to where now serial5 is
but I think two test pins for serial5, like for this JTAG thing would be kind of the easiest
then two test points/solder pads for serial5 would do it
ideally, CAN would get its own plug, and serial4 gets these pins, but that's probably not easily possible without major redesign
I myself would not mind if e.g. S7 and S8 would go to one of the 3-pin rows (i.e. no extra +VS for S7 and S8), serial 5 could then go to there (no +5V for serial5, but so what), and serial4 to where now serial5 is
but I think two test pins for serial5, like for this JTAG thing would be kind of the easiest