Hi all,
The online manual for the FVR command says
"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). "
Can anyone elaborate on that limitation? I don't mind if it's not accurate and I can offset the value, but I do mind if it fluctuates for some reason.
I'm trying to read a hall effect current sensor that has two output pins. One pin is 2.5V reference, and the other pin is the analog out which is + or - 600mV from the reference.... so it can read positive and negative current flow.
So I was going to set the negative reference on the picaxe as the 2.5V reference, and was going to use FVR1.024. This would give me enough resolution to use the sensor without any opamps, all be it for positive currents only.
The online manual for the FVR command says
"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). "
Can anyone elaborate on that limitation? I don't mind if it's not accurate and I can offset the value, but I do mind if it fluctuates for some reason.
I'm trying to read a hall effect current sensor that has two output pins. One pin is 2.5V reference, and the other pin is the analog out which is + or - 600mV from the reference.... so it can read positive and negative current flow.
So I was going to set the negative reference on the picaxe as the 2.5V reference, and was going to use FVR1.024. This would give me enough resolution to use the sensor without any opamps, all be it for positive currents only.