PBP doesn't support floating point, but you don't really need it for A/D
conversions.

For 8-bit A/D you can do something like this;

Quanta CON 5000 ' set this to +Vref. @5V use 5000. @4.990V 4990, etc.

Read the A/D value

ADCIN 0,ADval ' read RA0 A/D into word var ADval

ADval = ADval */ Quanta ' use middle 16-bits of multiplication.

LCDOUT DEC ADval DIG 3,".",DEC3 ADval ' 5.000, 3.962, etc,,

For 10-bit;

Quanta CON 1251 ' If +Vref = 5V.

To find Quanta take +Vref / 1023.

If +Vref = 5V then 5 / 1023 = 4.887mV.
4.887mV * 256 = 1.251 or 1251 for Quanta.

You can tweak the Quanta value to improve results. It may vary slightly from
PIC to PIC, but you want a good solid +Vref.