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Applies to: A51 Macro Assembler


Information in this article applies to:


When I assemble a small assembler file, I receive the following error message:

A51 Fatal Error -
  Error:  Limit Exceeded: Source Line Length (500)
A51 Terminated.

I have checked the source file several times, but I have no lines that are longer than about 50 characters. What could cause this problem?


If you receive this error, it typically indicates that there is a line that is longer than 500 characters.

If you program appears correctly in uVision2, check to see if there are CR's in the file that are not immediately followed by LF's. The A51 assembler must see a CRLF at the end of each source line.

You can verify this by opening the source file in Notepad and checking to see if some of the lines of the source file are listed on a single line.

In notepad, a CR that is not followed by a LF will appear as a little box.


To correct this problem, edit the file in Notepad and replace the box characters with a RETURN.

Article last edited on: 2000-10-05 00:00:00

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