diff --git a/runtime/adainclude/interfaces-rp2040-pio.ads b/runtime/adainclude/interfaces-rp2040-pio.ads
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+package Interfaces.RP2040.PIO is
+
+   type Bit is range 0 .. 1;
+   for Bit'Size use 1;
+
+   type Bit_32 is mod 2**32;
+   for Bit_32'Size use 32;
+
+   type Bit_Array is array (Natural range <>) of Bit
+      with Pack;
+
+   type CTRL_Type is
+      record
+         SM_Enable : Bit_Array (0 .. 3);
+         SM_Restart : Bit_Array (0 .. 3);
+         CLKDIV_Restart : Bit_Array (0 .. 3);
+         Reserved : Bit_Array (0 .. 19);
+      end record
+        with Object_Size => 32, Bit_Order => System.Low_Order_First;
+
+   for CTRL_Type use
+      record
+         SM_Enable at 0 range 0 .. 3;
+         SM_Restart at 0 range 4 .. 7;
+         CLKDIV_Restart at 0 range 8 .. 11;
+         Reserved at 0 range 12 .. 31;
+      end record;
+
+   type FSTAT_Type is
+      record
+         RXFULL : Bit_Array (0 .. 3);
+         Reserved_4_7 : Bit_Array (4 .. 7);
+         RXEMPTY : Bit_Array (8 .. 11);
+         Reserved_12_15 : Bit_Array (12 .. 15);
+         TXFULL : Bit_Array (16 .. 19);
+         Reserved_20_23 : Bit_Array (20 .. 23);
+         TXEMPTY : Bit_Array (24 .. 27);
+         Reserved_28_31 : Bit_Array (28 .. 31);
+      end record
+        with Object_Size => 32, Bit_Order => System.Low_Order_First;
+
+   for FSTAT_Type use
+      record
+         RXFULL at 0 range 0 .. 3;
+         Reserved_4_7 at 0 range 4 .. 7;
+         RXEMPTY at 0 range 8 .. 11;
+         Reserved_12_15 at 0 range 12 .. 15;
+         TXFULL at 0 range 16 .. 19;
+         Reserved_20_23 at 0 range 20 .. 23;
+         TXEMPTY at 0 range 24 .. 27;
+         Reserved_28_31 at 0 range 28 .. 31;
+      end record;
+
+   type PIO_Type is
+      record
+         CTRL : CTRL_Type;
+         FSTAT : FSTAT_Type;
+      end record;
+
+   for PIO_Type use
+      record
+         CTRL at 0 range 0 .. 31;
+         FSTAT at 1 range 0 .. 31;
+      end record;
+
+   type Direct_PIO_Type is
+      record
+         CTRL : Bit_32;
+         FSTAT : Bit_32;
+      end record;
+
+   PIO_1 : PIO_Type
+      with Address => PIO_1_Base, Volatile;
+
+   Direct_PIO_1 : PIO_Type
+      with Address => PIO_1_Base, Volatile;
+
+end Interfaces.RP2040.PIO;