Full FW16 input module specifications

[MJ1]

For the numpad you can find methods here

@MJ1

The macropad shares code with the numpad, so the numpad method of “Hold down keys for 2 and 6 while installing the module” works.
Bootmagic reset to bootloader, Hold numlock key (row 2, column 1 key) while inserting the module.

     *         ┌────┬────┬────┬────┐
     *   row 1 │Esc │Calc│ =  │ <- │
     *         ├────┼────┼────┼────┤
     *   row 2 │ Num│ /  │ *  │ -  │
     *         ├────┼────┼────┼────┤
     *   row 3 │ 7  │ 8  │ 9  │ +  │
     *         ├────┼────┼────┼────┤
     *   row 4 │ 4  │ 5  │ 6  │ +  │
     *         ├────┼────┼────┼────┤
     *   row 5 │ 1  │ 2  │ 3  │Entr│
     *         ├────┼────┼────┼────┤
     *   row 6 │ 0  │ 0  │ .  │Entr│
     *         └────┴────┴────┴────┘

Last option I can think of, the qmk_hid tool can trigger bootloader mode. github.com/FrameworkComputer/qmk_hid

For a regular keyboard holding down Both left-Alt and right-Alt while installing the module is one way
Custom QMK firmware? - #14 by MJ1
Also, remember to clear persistent memory after flashing, unless you’ve disabled Via entirely
Custom QMK firmware? - #31 by MJ1