• State Not Answered
  • Locked Locked
  • Replies 3 replies
  • Subscribers 21 subscribers
  • Views 775 views
  • Users 0 members are here
2025 survey

We are running a survey to help us improve the experience for all of our members. If you see the survey appear, please take the time to tell us about your experience if you can.

Options
Related
How was your experience today?
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Stack issue.

Mill Michael

Hi ALL,
I using STARTUP.A51 in my C51 Project,It will be start the sp at 0x07, becuase I define many idata in my program.When Call a function in C program, The idata overlap the push value make program counter jmup to error address when in debug mode.
Why the compilier don't auto setting stack ?

Thanks.

  • 0

    "Why the compilier don't auto setting stack ?"

    Because it doesn't have enough info to do so!

    The Compiler sees only one source file at a time; it does not know how many other modules may (or may not) be included in your project and, therefore, has no idea what else might be using IDATA!

  • 0 in reply to Andy Neil

    Thanks a lot.
    So, How to avoide the event appear when idata overlap stack value.I try to modify the sp, but it seem not good solution for the problem.

  • 0 in reply to Mill Michael

    Hi Free,

    How about modifing the following code in startup.a51:

    ?STACK		SEGMENT   IDATA

		RSEG	?STACK
		DS		64

		MOV	SP,#?STACK-1

    Acturally your stack pointer will be put at the end of idata address you are using. If you got a compile error to tell you that idata overlaps, then you have to shorten your statck length.
    It should be easy to understand when you have a look at the *.m51 file.

    Frank Hu