I try to simulate the operation of the PCF8523 in the alarm mode. The component should normally generate an interruption when the value of the « Minute_time » and « Hour_time » registers is respectively identical to that of « Minute_alarm » and « Hour_alarm » registers.
To obtain this operation, the AIE bit of the « Control_1 » register must be set to 1 (Control_1 = 0x02) and the CLKOUT output should be disabled by putting the COF bits [2:0] to 1 (TMR_CLKOUT_CTRL = 0x38).
With my program, the date is set at 26-03-2021, the time at 20:45:00 and the alarm at 20:51.
The examination of the internal registers of the PCF8523 shows that they are correctly programmed, but instead of generating an interruption at 20:51, the circuit generates this interruption every second (as if the SIE bit of the « Control_1 » register was set to 1).
When I put the same program on an Arduino Uno to control a « real » PCF8523, the circuit reacts correctly and generates the interruption at 20:51.
Could you check why the PCF8523 simulation model does not behave like the real component ?
Thanks for your help.
Best regard.
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