PCW CCS: Return from assembly function ?

[eng_amr]

Hi,

I have a assembly function like that

void myfunc (void)
{

#asm
" // my assembly lines
"
return
"
"
return
#endasm

}

I want to know how can i return from the assembly function .
I tried the _return_ found it in the manual.
But it give me this error Undefined identifier _return_
And how can i return with a value in assembly function ?

Thanks
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515928

[PCM programmer]

:=I want to know how can i return from the assembly function .
:=And how can i return with a value in assembly function ?
--------------------------------------------------------
How about this:

<PRE>
#include "c:\Program Files\Picc\Devices\16F877.H"
#fuses HS, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
#use delay(clock = 8000000)
#use rs232(baud = 9600, xmit=PIN_C6, rcv = PIN_C7, ERRORS)
<BR>
char test(char value);
<BR>
//======================================================
void main()
{
char c;
<BR>
c = test(0x20);
<BR>
while(1);
}
//=======================================================
<BR>
char test(char value)
{
#asm
movlw 0x08 // This is the return code for this test.
btfsc value, 0 // Is bit 0 of value set ?
goto done // If so, return 0x08
<BR>
movlw 0x40 // This is the return code for this test.
btfsc value, 1 // Is bit 1 of value set ?
goto done // If so, return 0x40
<BR>
// etc.
<BR>
movlw 0x00 // Default return value
done:
movwf _return_ // Put the return value into _return_
#endasm
<BR>
}
</PRE>

Note: The tests, and the return codes are completely arbitrary
and are just shown to demonstrate the idea.
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515929

[eng_amr]

Hi,

Thanks your code works fine but when i try to compile my code it state that error "Undefined identifier _return_ "

here is my code

#include <16F84.h>
#Case

#fuses XT,NOWDT,NOPROTECT,PUT
#use delay (clock=4000000)
#byte portb=0x06
#byte porta=0x05

unsigned char Cntr,P_Val;

int Pulsin(void);


void main() {

int c;

// set_tris_b(0x00);
// set_tris_a(0xff);

c=Pulsin();


while(1);

}

int Pulsin(void)
{

// pulse measurement subroutine
#asm
Clrwdt // Walk the dog
Clrf Cntr // Clear the variables used,
Clrf P_Val // prior to the subroutine
Trans: Btfss porta,2 // Wait for a 1 to 0 transition
Goto Edge // Edge found!
Incfsz P_Val // Else, increment P-VAL until >255
Goto Trans
Incfsz Cntr // Loop until 255
Goto Trans
goto done
Edge: Clrf P_Val // A 1 to 0 transition occurred
Edge_LP: Btfsc porta,2 // Count how long it's logic 0
goto done
Clrwdt // Walk the dog
Nop // Timing loop
Nop
Nop
Nop
Nop
Incfsz P_Val // Increment P_VAL until >255
Goto Edge_LP
done:
movf P_Val,w
movwf _return_

#endasm
}






:=:=I want to know how can i return from the assembly function .
:=:=And how can i return with a value in assembly function ?
:=--------------------------------------------------------
:=How about this:
:=
:=<PRE>
:=#include "c:\Program Files\Picc\Devices\16F877.H"
:=#fuses HS, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
:=#use delay(clock = 8000000)
:=#use rs232(baud = 9600, xmit=PIN_C6, rcv = PIN_C7, ERRORS)
:=<BR>
:=char test(char value);
:=<BR>
:=//======================================================
:=void main()
:={
:=char c;
:=<BR>
:=c = test(0x20);
:=<BR>
:=while(1);
:=}
:=//=======================================================
:=<BR>
:=char test(char value)
:={
:=#asm
:=movlw 0x08 // This is the return code for this test.
:=btfsc value, 0 // Is bit 0 of value set ?
:=goto done // If so, return 0x08
:=<BR>
:=movlw 0x40 // This is the return code for this test.
:=btfsc value, 1 // Is bit 1 of value set ?
:=goto done // If so, return 0x40
:=<BR>
:=// etc.
:=<BR>
:=movlw 0x00 // Default return value
:=done:
:=movwf _return_ // Put the return value into _return_
:=#endasm
:=<BR>
:=}
:=</PRE>
:=
:=Note: The tests, and the return codes are completely arbitrary
:=and are just shown to demonstrate the idea.
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515942

[PCM programmer]

<font face="Courier New" size=-1>:=
:=Thanks your code works fine but when i try to compile my code it state that error "Undefined identifier _return_ "
--------------------------------------------------------

The problem is caused by using the #case statement, while
typing _return_ with lower case letters.

If you compile with the +LS option, you can see the symbol
table at the end of the MPLAB .LST file. The symbol table
spells it as: _RETURN_

So if you use #case, you must use upper case, like this:

movwf _RETURN_</font>
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515962