Radio Shack PC-2 TRS-80 Owner's Manual page 83

POINT will return a number between 0-255. If 0 is returned, then there are not any dots turned on in the specified
column. If 255 (or 127) is returned, all of the dots in the specified column are turned on. 255 will be returned if
you specified GPRINT 255 or FF and 127 will be returned if you specified GPRINT 127 or 7F.
The number the PC-2 returns will identify the dot pattern specified with GPR INT. For instance, if your program
uses GCURSOR 100 and you specified GPRINT 8, the PC-2 will return the value of 8 when you enter POINT 100.
For details on specifying dot patterns, see GPR INT.
Example
The following program randomly moves the GCURSOR position among the first 10 columns. It GPRINTs pattern
8 (a single dot). The program then tests whatever column you specified and tells you whether or not a dot is on
in the column.
20: GCURSDR RND(10)
30: A=F'DIr-H C
35:
IF A)·O THEN
GD~;UB
100
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