The screen editor has something called the "line link" table. Whenever a character is printed to the 40th column the line link table is updated. A bit is set that "links" the line to the one below it. This table is updated when the screen is scrolled as well. I did some work understanding this for the PET's editor rom. You can find a commented disassembly here: https://github.com/sjgray/cbm-edit-rom/blob/master/disassemblies/edit-4-40-n-60Hz-901499-01-linelink%20analysis.txt The C64's code is based on this but will be slightly adapted. Hope it helps. Steve From: "Ruud@Baltissen.org" <Ruud@Baltissen.org> To: cbm-hackers@musoftware.de Sent: Saturday, February 11, 2017 1:40 PM Subject: Two lines on the screen = one BASIC line Hallo allemaal, A thing I haven't figured out yet: How does BASIC know that two lines on the screen (of a C64) belong to one BASIC line? -- Kind regards / Met vriendelijke groet, Ruud Baltissen www.Baltissen.org --- Dit e-mailbericht is gecontroleerd op virussen met Avast antivirussoftware. https://www.avast.com/antivirus Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2017-02-11 22:00:23
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