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Geoffg

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Joined: 06/06/2011
Location: Australia
Posts: 3308

Posted: 05:18pm 08 Jul 2017

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twofingers said Can I call a MMBasic function from within a Cfunction?

Yes, use the RunBasicSub(string) function defined in CFunctions.h

The argument to RunBasicSub is a string specifying the name of the user defined BASIC subroutine to be executed. It MUST be terminated with TWO null chars.

Typical C code:

char s[5];
s[0] ='F'; s[1] ='o'; s[2] ='o'; s[3] = 0; s[4] = 0;
RunBasicSub(s);

Corresponding BASIC function:

SUB Foo
PRINT "Hello World from a CFunction"
END SUB

GeoffEdited by Geoffg 2017-07-10

Geoff Graham - http://geoffg.net

twofingers

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Joined: 02/06/2014
Location: Germany
Posts: 1671

Posted: 03:10am 09 Jul 2017

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Hi Geoff,

Thanks a lot for your quick response!

Geoffg said

twofingers said Can I call a MMBasic function from within a Cfunction?

Yes, use the RunBasicSub(string) function defined in CFunctions.h

Unfortunately the CFunctions.h is poor documented. (Not a criticism!)

Peters useful documentation "Brief overview of all of the facilities in Cfunctions.h" (released 27. February 2016) is unfortunately somehow outdated.

Undocumented in Cfunctions.h:

#define GetTouchAxisVector (*(unsigned int *)Vector_GetTouchAxis)
#define GetTouchAxis ((int (*)(int)) (*(unsigned int *)GetTouchAxisVector)) (a)

// NOTE: The argument to RunBasicSub is a string specifying the name of the BASIC subroutine to be executed.
// It MUST be terminated with TWO null chars.
#define RunBasicSub(a) ((void (*)(char *)) Vector_ExecuteProgram) (a)

#define SaveProgramToFlash(a,b) ((void (*)(char *, int)) Vector_SaveProgramToFlash) (a,b)
#define error(a) ((void (*)(char *)) Vector_error) (a)
#define ProgFlash ((int *) Vector_ProgFlash)
#define ClearProgram() ((void (*)(void)) Vector_ClearProgram) ()
#define llist(a,b) ((char * (*)(char *, char *)) Vector_llist) (a,b)
#define CFuncInt2 (*(unsigned int *) Vector_CFuncInt2)

Maybe it would be useful to include the (updated) documentation in your MMBasic distribution?

Geoffg said The argument to RunBasicSub is a string specifying the name of the user defined BASIC subroutine to be executed. It MUST be terminated with TWO null chars.

Typical C code:

char s[5];
s[0] ='F'; s[1] ='o'; s[2] ='o'; s[3] = 0; s[4] = 0;
RunBasicSub(s);

Corresponding BASIC function:

SUB Foo
PRINT "Hello World from a CFunction"
END SUB

Geoff

Just out of curiosity: Is there also a way to pass arguments?

Regards
MichaelEdited by twofingers 2017-07-10

causality ≠ correlation ≠ coincidence

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10565

Posted: 05:14am 09 Jul 2017

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Quote Just out of curiosity: Is there also a way to pass arguments?

You don't need to:

Set up a normal Basic variable with Global scope
Pass it to the Cfunction
manipulate it in the CFunction as required
Call the MMBasic function which has by definition got access to the Basic variable

twofingers

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Joined: 02/06/2014
Location: Germany
Posts: 1671

Posted: 05:21am 09 Jul 2017

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Thanks Peter!

Sometimes the things can be so simple!

Michael

causality ≠ correlation ≠ coincidence

crez

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Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 07:55pm 26 Oct 2017

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Further back in this thread someone sorted out a problem by switching to xc32 compiler version 1.33. I can not find this for download from microchip, only 1.44. I am getting the same sort of error. Where do I go from here? My entry into C functions has not been smooth so far!

DavidEdited by crez 2017-10-28

JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 4126

Posted: 08:56pm 26 Oct 2017

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Maybe here

John

crez

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Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 01:47am 27 Oct 2017

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Thanks John, I'm back on track (for the moment

)

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