The Spectrum Next and the TBBlue can work with a standard PS/2 keyboard. The PS/2 function keys have additional functions as listed below:

F1 – Hard Reset
F2 – Toggle scandoubler
F3 – Toggle vertical frequency: 50/60 Hz
F4 – Soft Reset
F7 – Toggle scanlines
F8 – Toggle turbo mode
F9 – Multiface button (M1)
F10 – DivMMC button (Drive)

Some keys are mapped to ZX Spectrum keys, as listed below:

SHIFT – Caps Shift
CONTROL – Symbol Shift

PCBs with membrane keyboard (Next, Next boards inside original ZX Spectrums and VTrucco) can use the M1 action button as a “function button”: A single click load the Multiface software (if available and activated in boot menu). Pressing and holding the M1 button and selecting a key “1”, works like “F1” key. Key “2” as “F2” key and so on. This allows for using F1-F10 keys on the Next keyboard or with the original Spectrum keyboard.