Re: [cc65] Re: Questions for CBM guys

From: Mark J. Reed <>
Date: 2008-03-04 21:28:44
I think some folks are violently agreeing here.  The facts are these:

On Commodore 8-bit machines, all the way back to the PET, writing the
single byte $0D to the output channel attached to the display causes
the cursor to move all the way to the left and down one line.   This
behavior is in the ROM driver for the display device.  There is no
single character that you can write to the screen to cause the cursor
to move all the way to the left without going down one line.  However,
on the C-128 you can write the two-byte sequence $1B $4A (ESC + J) to
achieve that result.

Writing the single byte $0A to the display channel doesn't do anything
at all on the PET, VIC-20, or Commodore 64; if you want to move the
cursor down without changing its horizontal position, you use the
cursor down control ($11).  On the 128, $0A does have the same effect
as $11. (Dunno about the Plus/4 or C-16.  Anyone able to test?)

If you open an output channel with a secondary address >=128 on any of
these systems, then CR's written to that channel will automatically be
followed by LF, to support devices which require that (e.g. some
printers, esp. for the PET).
To unsubscribe from the list send mail to with
the string "unsubscribe cc65" in the body(!) of the mail.
Received on Tue Mar 4 21:28:59 2008

This archive was generated by hypermail 2.1.8 : 2008-03-04 21:29:02 CET