procedure write_cmos(regno:byte;newval:byte);
begin
  asm
    pushf
    cli
    mov al,regno
    out 70h,al
    mov al,newval
    out 71h,al
    popf
  end;
end;

function read_cmos(regno:byte):byte;
var
  regval : byte;
begin
  asm
    pushf
    cli
    mov al,regno
    out 70h,al
    in  al,71h
    mov regval,al
    popf
  end;
  read_cmos:=regval;
end;

const
  hexdigit : string[16] =('0123456789ABCDEF');

function b2h(b:integer):string;
begin
  if (b<0) or (b>255)
    then b2h:='__'
    else b2h:=hexdigit[(b shr 4)+1]+hexdigit[(b and 15)+1];
end;

type
  cmos_data = record
              array [0..$3F] of byte;
              chksum : word;
              end;
var
  cdat : cmos_data;
  r : byte;
begin
  for r:=$10 to $2d do
    begin
    t:=t+read_cmos(r);
    writeln('@',b2h(r),':',b2h(read_cmos(r)));
    end;
  writeln('Total = ',b2h(hi(t)),b2h(lo(t)));
  writeln('@2e:',b2h(read_cmos($2e)));
  writeln('@2f:',b2h(read_cmos($2f)));
end.