Mineoro FG79-Happy new Year

[J_Player]

Originally Posted by FrancoItaly

Hi J_Player

I don't know the AT89C2051 , I know very well the PIC 16F... series. Some PICs have 2 comparators and an internal programmable reference voltage, if it's the same for
the AT89C2051 it's possible that the processor controls if the voltage is out of a window voltage. Of course 2 externals comparator do the same job.

Best Regards

Hi FrancoItaly,
The AT89C2051 also has two internal comparators, one at each of the analogue inputs. The comparator uses bit 6 of port 3 (P3.6) for the comparator output result.
Because of this, P3.6 is not available for general purpose I/O.
Hmmmm.... I don't see port 3 connected to anything in the Mineoro circuit. There must be some coding in the AT89C2051 which extracts the gold signal.

Maybe one input is for fresh gold, and the other is for long-time buried gold.
Or maybe the AT89C2051 has a random number generator coded to make random beeps when it senses there is no signal is coming from the loop or ion chamber?

Best wishes,
J_P