Yes, Vpu is VDD or +5V.

If you have time, can you try this...
Code:
;-----------------------------------------------------------------------------
Done      VAR BIT
Parasite  VAR BIT
Family    VAR BYTE

Diag:
    OWIn DQ, 4, [Done]
    LCDOUT $FE,1,"Done =", bin1 Done
    
    OWOUT DQ, 1, [$CC, $B4] ' READ POWER SUPPLY
    OWIn DQ, 4, [Parasite]
    LCDOUT $FE,$C0,"Power="
    if Parasite = 0 then
        LCDOUT "Parasite"
    else
        LCDOUT "VDD"
    endif
    
    OWOUT DQ, 1, [$33]
    OWIN  DQ, 2,[Family]
    LCDOUT $FE,$89,"FAM=",IHEX2 Family
    
    PAUSE 1000
goto Diag
;-----------------------------------------------------------------------------
Just stick it before the main loop in your program.

Ideally, you should see this on the LCD ...
Code:
Done = 1  FAM=$10
Power=VDD
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