OK, this is what he say he needs to do:

So he's doing the familiar printer self-test pattern:

    0123456789abcdefghijklmnopqrstuvw
    xyzABCDEFGHIJKLMNOPQRSTUVWXYZ`!"£
    $%^&*()_+=-[{]}#~'@;:/?.>,<|0123
    456789abcdefghijklmnopqrstuvwxyzA
    BCDEFGHIJKLMNOPQRSTUVWXYZ`!"£$%^&
    etc, etc,...

This can be very easily implemented in a perfectly straightforward loop with no need for any timers, unstructured jumps, or other kludges:

character_to_print := first printable character -- Start with the 1st printable character in the printer's character set
characters_printed := 0;                        -- We haven't printed anything yet!

-- Infinite loop to continuously print all characters from the printer's character set,
-- inserting line breaks where required
repeat
{
   print character_to_print;

   -- Count another character printed;
   -- Check if we now need to insert a line break
   increment characters_printed;
   if characters_printed >= max characters per line then
   {
      print newline;
      characters_printed := 0 -- Now back at the start of a line
   }

   -- Prepare to print the next character from the character set;
   -- If we've just done the last character, start again at the first
   increment character_to_print;
   if character_to_print > last printable character then
   {
      character_to_print := first printable character 
   }
} forever

The above assumes a character printer, but exactly the same principle would apply if you're driving the dots directly - you just count columns instead of characters.


I didn't say it was incorrect; I said it was bad idea - especially when the aim can be achieved in such a simple & straightforward manner!