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------------------------------------------------------------------------------

with nRF.Device;
with nRF.TWI;

package body MicroBit.I2C is

   Init_Done : Boolean := False;

   Device : nRF.TWI.TWI_Master renames nRF.Device.TWI_0;
   --  This device should not conflict with the device used in MicroBit.SPI.
   --  See nRF Series Reference Manual, chapter Memory.Instantiation.

   -----------------
   -- Initialized --
   -----------------

   function Initialized return Boolean
   is (Init_Done);

   ----------------
   -- Initialize --
   ----------------

   procedure Initialize (S : Speed := S400kbps) is
   begin
      Device.Configure
        (SCL   => MB_SCL,
         SDA   => MB_SDA,
         Speed => (case S is
                      when S100kbps => nRF.TWI.TWI_100kbps,
                      when S250kbps => nRF.TWI.TWI_250kbps,
                      when S400kbps => nRF.TWI.TWI_400kbps)
        );

      Device.Enable;
      Init_Done := True;
   end Initialize;

   ----------------
   -- Controller --
   ----------------

   function Controller return not null Any_I2C_Port
   is (Device'Access);

end MicroBit.I2C;
