ADC

Package AVR.ADC

Package AVR.ADC provides a control API to the Analog to Digital Converter channels.

with Interfaces;                   use Interfaces;

package AVR.ADC is
   pragma Preelaborate;

   type Clock_Scale is new Unsigned_8 range 1 .. 7;

   Scale_By_2    : constant Clock_Scale := 1;
   Scale_By_4    : constant Clock_Scale := 2;
   Scale_By_8    : constant Clock_Scale := 3;
   Scale_By_16   : constant Clock_Scale := 4;
   Scale_By_32   : constant Clock_Scale := 5;
   Scale_By_64   : constant Clock_Scale := 6;
   Scale_By_128  : constant Clock_Scale := 7;

   type Reference_Voltage is
     (Ext_Ref,   --  provide external reference voltage to AVCC pin
      Is_Vcc,    --  use Vcc (typ. 5V or 3.3V) as reference
      Int_Ref);  --  typ. 2.56V or 1.1V, see data sheet

   Max_ADC_Channels : constant := 8;

   type ADC_Channel_T is new Unsigned_8 range 0 .. Max_ADC_Channels - 1;

   --  result type of the AD conversion
   subtype Conversion_10bit is Unsigned_16 range 0 .. 2**10 - 1;
   subtype Conversion_8bit is Unsigned_8;

   procedure Set_Prescaler (Scale : Clock_Scale);
   procedure Set_Reference (Ref : Reference_Voltage);

   procedure Init (Scale : Clock_Scale; Ref : Reference_Voltage);


   procedure Start_Conversion (Ch : ADC_Channel_T);
   function Conversion_Is_Active return Boolean;
   function Last_Result return Conversion_10Bit;
   function Convert_10bit (Ch : ADC_Channel_T) return Conversion_10bit;
   function Convert_8bit (Ch : ADC_Channel_T) return Conversion_8bit;

end AVR.ADC;