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PRINT AT 22,0 - Printable Version

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PRINT AT 22,0 - patters - 01-27-2021

Is it normal that the entire screen scrolls every time I print at line 22 - not even filling the line? Surely it should behave like the other lines, no? Or else it's not much of an improvement over Sinclair BASIC's PRINT #0; AT 1,0;


RE: PRINT AT 22,0 - boriel - 01-27-2021

(01-27-2021, 06:57 PM)patters Wrote: Is it normal that the entire screen scrolls every time I print at line 22 - not even filling the line? Surely it should behave like the other lines, no? Or else it's not much of an improvement over Sinclair BASIC's PRINT #0; AT 1,0;

No, it should now scroll up until you print at 23, 0 and fill the line or put no semicolon. i. e.
Code:
PRINT AT 22, 0; "22"
PRINT "at 23";
print " ... and More";
pause 0
This program won't scroll the screen (just tested).
ZX Basic uses 0 to 23 coordinates.
To mimic Sinclair BASIC screen behaviour the scroll starts just before printing the next character that should go in "line 24".
In other words:
Code:
PRINT AT 23, 0; "Hello world" : REM no ; at the end, will scroll
PAUSE 0
REM screen will scroll up just before printing this
PRINT "This is now at line 23"

You can disable scroll entirely if compiling with -D DISABLE_SCROLL


RE: PRINT AT 22,0 - patters - 01-28-2021

Thanks, I will have to try and isolate a test case. If not I'll just have to PM you with my entire source.