Atari 800 Basic Reference Manual

TRAP (T.)
22 Program Stateme nt s
and B, because of the RESTORE statement, will still equal 30. Therefore, the
PRINT statement in line 50 will display SUM TOTAL EQUALS 45.
Format:
Example:
TRAP aexp
100 TRAP 120
The TRAP statement is used to direct the program to a specified line number if
an error is detected . Without a TRAP statement, the program stops executing
when an error is encountered and displays an error message on the screen.
The TRAP statement works on any error that may occur after it has been ex-
ecuted, but once an error has been detected and trapped, it is necessary to reset
the trap with another TRAP command. This TRAP command may be placed at
the beginning of the section of code that handles input from the keyboard so
that the TRAP is reset after each error. PEEK(195) will give you an error
message (see Appendix B). 256 *PEEK(187)+ PEEK(186) will give you the number
of the line where the error occurred. The TRAP may be cleared by executing a
TRAP statement with an aexp whose value is from 32767 to 65535 (e.g., 40000).

Atari 800 Specifications

General

Brand	Atari
Model	800
Category	Desktop
Language	English