home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Loadstar 7
/
007.d81
/
pps #15
< prev
next >
Wrap
Text File
|
2022-08-26
|
1KB
|
69 lines
PEEKs, POKEs, and SYSes -- Part 15
by Jimmy Weiler
======================================
Location:217-242 Hexadecimal: $00d9-f2
Official Label: LDTB1 Type: RAM
Useful BASIC commands: PEEK, POKE
======================================
LDTB1 is the screen line link table.
It keeps track of which screen lines
are logically connected to their
neighbors.
When you LIST a program with long
lines or PRINT anything longer than 40
characters, two adjacent lines are
always logically 'connected' and are
used as one line until you disconnect
them. The linking of lines is vital
when you're programming, but annoying
when you are trying to format a screen
of text.
You can tell when your lines are
linked because carriage returns will
tend to move down two physical lines
instead of just one.
If you want to disconnect all the
lines of the screen, all you need to
do is run this line of code:
1000 FOR L = 217 to 242: POKE L,128 OR
PEEK (L): NEXT
Be careful what you poke into LDTB1.
Inappropriate values can scramble your
screen completely.
--------------------------------------