Aha, to som nevedel...
Takže potom asi takto:

function lowcase(c : char) : char;
begin
if (c >= #65) and (c <= #90) then
   lowcase := chr(ord(c) + 32)
else
   lowcase := c;
end;

begin
  repeat
    clrscr;
    writeln('Zadaj text');
    readln(name);
    for count := 1 to length(name) do
    begin
      if (name[count] >=#65) and (name[count] <=#90) then
         name[count] := lowcase(name[count])
      else
         name[count] := upcase(name[count]);
    end;
    writeln(name);
  writeln;
  write('Chceš pokračovať? (A/N) ');
      readln(answer);
until upcase(answer)='N';

end.