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John Earland · 21st Feb 2020, 10:57 pm

I found this on the web:
SYNTAX ERROR on every command and screen scrolling problems: I read of a case where on every command entered the system reacted with a "SYNTAX ERROR". Also when scrolling the screen, some characters change. This is a problem when the main CPU reads the video screen. When a command is entered, it is read from screen, not from some buffer memory. Also when the screen is scrolled, the data is read from the screen and written back to it. So both problems came from the same source, the bus driver that separated the video RAM from the CPU bus. It had a broken driver in one of the lines.

Any use?

21st Feb 2020, 10:57 pm	#126
John Earland Hexode Join Date: May 2013 Location: Middlesbrough, North Yorkshire, UK. Posts: 442	Re: Commodore PET 3016 I found this on the web: SYNTAX ERROR on every command and screen scrolling problems: I read of a case where on every command entered the system reacted with a "SYNTAX ERROR". Also when scrolling the screen, some characters change. This is a problem when the main CPU reads the video screen. When a command is entered, it is read from screen, not from some buffer memory. Also when the screen is scrolled, the data is read from the screen and written back to it. So both problems came from the same source, the bus driver that separated the video RAM from the CPU bus. It had a broken driver in one of the lines. Any use?