I like my projects to be aware of the battery voltage that is driving the PICAXE. In the past, I've hooked a 2.5v regulator up to one of the ADC pins and, then measured the ADC value. Since the PICAXE ADC changes with source voltage, but the pin voltage is constant because of the regulator, I have a way to sense the source voltage.
But I'm now running my projects at 2.5v or less, so the regulator trick isn't ideal. I can look for a lower voltage regulator, but I'm wondering if there's an even easier way to do this, possibly with a single component such as a zener diode. Or, even better, perhaps there's some trick of the new 08M2 devices such as a twisted use of the READINTERNALTEMP command. I'd be surprised if this function wasn't already available at the PIC level.
Any ideas on the simplest way to sense the PS voltage that will work down to 1.8v? As always, thanks in advance for any ideas.
But I'm now running my projects at 2.5v or less, so the regulator trick isn't ideal. I can look for a lower voltage regulator, but I'm wondering if there's an even easier way to do this, possibly with a single component such as a zener diode. Or, even better, perhaps there's some trick of the new 08M2 devices such as a twisted use of the READINTERNALTEMP command. I'd be surprised if this function wasn't already available at the PIC level.
Any ideas on the simplest way to sense the PS voltage that will work down to 1.8v? As always, thanks in advance for any ideas.