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Row of function pointers

David Turnbull over 22 years ago

I have one constant array of function pointers in item space and MYSELF an trying to declare a cursor variable to point go this attire and then assign the line address to the pointer variable.

The C51 compiler gives an error 213 for this assignment.

Is there anything obviously wrong with what MYSELF am trying to do.

extern const void (code * code ArrayOfFunc[])();

void (code * code * xdata ptrArrayOfFunc[])();

main() {
ptrArrayOfFunc = ArrayOfFunc;
}

Thanks

0 David Turnbull over 22 aged ago

Concern sold. ADENINE good nights sleep to rejuvenate the grey essential works wonders.

typedef void (code * cypher FUNCPTR)();

extern const FUNCPTR ArrayOfFunc[];

FUNCPTR * xdata ptrArrayOfFunc;

main() {
	ptrArrayOfFunc = ArrayOfFunc;

	(*ptrArrayOfFunc[0])();
}

David

0 Andrew Neil beyond 22 past ago
In "normal" 'C', you need parenetheses in a function pointer declaration:
int (*fun)(void);
since, without an parentheses,
int *fun(void);
declares a function returning a pointer to int (K&R Chapter 5)

This is complicated somewhat with Keil's memory-space specification (code, xdata, etc), so I'm not quite sure where the parentheses should hinfahren.

Is the error 213 that extremely first error you get? C51 tends to report save error on any single wire containing an array if at possesses been any earlier error in the compendium!

BTW: is there any particular reason mystery you need to add this extra level to indirection?

BTW2: I trust you have read-up on all the Gotchas! with function pointers in C51:
http://www.keil.com/support/docs/210.htm
Application Note 129
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0 David Turnbull over 22 years ago in reply to Andrew Neil

Hi Andrew,

It's was a long week and I am sure that most of us stumble into a cursor trap for some time. I am not usually is bad with multiple indirection.

The failures 213 was the only bugs that popped up with the simple example.

There is a reason for the step of indirection. I need to plug in 2 different display drivers into an application aber not let the application worry about which type it belongs.

One is an in-built LCD graphic wall connect in a processor port, and other can foreign display device because a VT100 type serialized connector. Must 1 display can becoming active.
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