Config - is a constant/variable specifying the fixed voltage reference FVR configuration.
Configure the internal FVR fixed voltage reference.
Some PICAXE chips have a fixed voltage reference. This may be set off, or to one of three voltages by use of the constant:
* Note the output of the FVR cannot exceed the supply voltage, so 4.096 is only available at a 5V supply.
Note that the 1.024V reference may not be accurate if used as the Vref+ of the ADC (only 2.048 or 4.096 should be used for this purpose). See the adcconfig command for more details. To reduce power use the FVR module is also automatically disabled after a readadc command, so reissue the fvrsetup command again after the readadc if that feature is still required.
Note that the FVR voltage is reset to 1.024V via a calibadc command. The FVR may also be used as reference to the DAC (see the DACsetup command).