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```Is this elegant enough?

procedure Test_Register_Bits
is
type Register_Bits_Type is array (Natural range 0 .. 7) of Boolean;
pragma Pack (Register_Bits_Type);

type Octet_Type is mod 256;

(Source => Octet_Type,
Target => Register_Bits_Type);

(Source => Register_Bits_Type,
Target => Octet_Type);

Register_Bits : Register_Bits_Type;
Octet         : Octet_Type;

begin
-- Set all of the odd-numbered bits true, even-numbered bits false;
for B in Register_Bits'Range loop
Register_Bits (B) := B mod 2 = 1;
end loop;

-- Copy the register bits to an octet;
Octet := To_Octet (Register_Bits);

-- See what we have;
for B in Register_Bits'range loop
("Bit" & Natural'Image (B) & " is on? " &
Boolean'Image (Register_Bits (B)));
end loop;
("Register contents:" & Octet_Type'Image (Octet));

-- Now, set the octet value to 96
Octet := 96;

-- Copy the octet to the register bits
Register_Bits := To_Bits (Octet);
-- See what we have;
for B in Register_Bits'range loop
("Bit" & Natural'Image (B) & " is on? " &
Boolean'Image (Register_Bits (B)));
end loop;
("Register contents:" & Octet_Type'Image (Octet));

end Test_Register_Bits;

To "Mask" modular types, simply use the and, or, and xor
operators on operands of the same type.

----- Original Message -----
Sent: Monday, April 15, 2002 1:11 AM
Subject: Some questions on record attributes

Hi,
for the development for the port parallel interface, I've planned to map the
unsigned_8 value to a record of bits of type (on,off).
Do you know how to mask an integer or unsigned_8?

As far as I haven't found an ellgant way I've done this:

I've the next definitions:

type flag is (on, off);

type Registro_Byte is
record
Bit0,
Bit1,
Bit2,
Bit3,
Bit4,
Bit5,
Bit6,
Bit7 : Flag;
end record;

data : registro_byte;
register : unsigned_8;

(...) I load an 8-bit integer into the register:

register:= 128; (this is done via DOSPORTS libraries)

I want data to be a map of the register bit:

if Integer (Shift_Right (register , 0) mod 2 ) = 1 then
data.Bit0 := On;
else
data.Bit0 := Off;
end if;

if Integer (Shift_Right (register , 1) mod 2 ) = 1 then
data.Bit1 := On;
else
data.Bit1 := Off;
end if;

and so on 'til BIT7.

Do you know how to assign the values using a loop?

I don't know how to do a loop that works like the next false one:

for ix in 0..7 loop
if Integer (Shift_Right (register , ix ) mod 2 ) = 1 then
data.BIT(ix) := On; -- wrong line
else
data.Bit(ix) := Off; -- wrong line
end if;
end loop;