06-14-2016, 09:23 PM
boriel Wrote:This behaviour is expected.I understand and have to check where my original BASIC program "runs out of screen".
The ZX Spectrum screen has only 24 physical rows (from 0 to 23). Printing beyond 23 just wraps around and resets the X coordinate (back to 0).
It also puts an "Out Of Screen" signal in the ROM Variable, hence when you exit back to Sinclair BASIC you get the 5 Out of Screen Error.
This is done this way because you can check if your latest print has been out of screen or not.
However, one question:
When I have a program with this two lines:
PRINT AT 24,0;"24,0"
PRINT AT 10,0;"10,0"
I too get the 5 Out of Screen Error, and the second "regular" PRINT position
donĀ“t reset the "Out Of Screen" signal ROM Variable (is this a Spectrum BASIC system variable ?).
I think a regular PRINT position should reset the "Out of Screen" flag ?
Regards,
Luzie