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Posted By

SVS
on 2008-12-24
05:49:34
 TRAP command

Who does know how errors are intercepted by TRAP command? Maybe it uses the stack like GOSUB or FOR..NEXT?
I'm asking you for this, because I'm facing a critical problem after TRAP has managed an error situation.
Thank you for tips and help.

Posted By

JamesC
on 2008-12-24
09:22:16
 Re: TRAP command

When a BASIC error is encountered, BASIC checks the TRAP line locations at $04F2-04F3 to see where to jump for error handling. These locations are set at power-up to 00 FF.

If a different line number is found, BASIC goes to that line. Otherwise, the standard error procedure (halt program and display error) is performed.

ER is stored in $04EF and EL is stored in $04F0-04F1.



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