Re: updating a hardware cursor with assembly and ada

[cl1 <charles.w.lambert@gmail.com>]

Okay I have updated the Update_Cursor method with the following
implementation, However I am getting the error:

i386-elf-gcc -fno-pic -c -nostdinc -ffunction-sections -fdata-sections
-I. -gnato -gnatp -gnatE vga.adb
vga.adb:3:06: "System.Machine_Code" is not a predefined library unit

I know the error message means there is no System.Machine_Code that it
can find. What i don't know is if there is a flag, or something i can
do to get access to it. I'm really lost at this point, because there
is no way i can implement that package with my current knowledge.


with System;
with Interfaces;
with System.Machine_Code;
package body Vga is
   ...
 
-----------------------------------------------------------------------------
   procedure Update_Cursor (Console : Video_Console) is
      use Interfaces;
      use System.Machine_Code;
      Data : Unsigned_16 := Console.Column * 80 + Console.Row;
      OutB : String := "outb 140x3D4, 14" & NL & "outb %0, 0x3D5";
      Part1 : Unsigned_8 :=
Ada.Unchecked_Conversion(Shift_Right(Data));
      Part2 : Unsigned_8 := Ada.Unchecked_Conversion(Data);
   begin
      Asm (Template => "outb 14, 0x3D4" & NL
                     & "outb %0, 0x3D5" & NL
                     & "outb 15, 0x3D4" & NL
                     & "outb %1, ox3D5",
           Input    => (Unsigned_8'Asm_Input(Part1),
                        Unsigned_8'Asm_Input(Part2));
   end Update_Cursor;
 
-----------------------------------------------------------------------------
   ...
end Vga;