no match for ‘operator=’ in ‘((sync_fifo*)this)->sync_fifo::wptr = 0’

[Rashmi11]

Hi All ,

I am new to SytemC  and I am designing a FIFO . When I run the make file I am getting an error " no match for ‘operator=’ in ‘((sync_fifo*)this)->sync_fifo::wptr = 0’ " .  I guess this has do with the sensitivity list  of wptr and rptr but I am not sure how to fix it.I have highlighted the lines where I am getting error . It will be really helpful if someone could explain this .  Thank you

 

#include <systemc.h>  

 

SC_MODULE (sync_fifo){

sc_in_clk clk;

sc_in<bool> rst;

sc_in<bool> rd_wr;

sc_out<bool> full;

sc_out<bool> empty;

sc_in < sc_uint<8> > data_in;

sc_in < sc_uint<4> > wptr;

sc_in < sc_uint <4> > rptr;

sc_out < sc_uint<8> > data_out;

 

sc_uint<8> ram_data[256];

 

 

void read_write() {

if(rst == 1)

{

wptr=0;rptr=0;data_out=0;

}

else

if(rd_wr == 1 && !full)

{

ram_data[wptr.read()]=data_in;

wptr=wptr+1;

}

else

if(rd_wr == 0 && !full)

{

data_out=ram_data[rptr.read()];

rptr=rptr+1;

}

}

 

void emp_ful(){

if(rst == 1)

{

full=0;

empty=0;

}

else

{

if(wptr == rptr )

{

empty=1;

}

else if((wptr - rptr) == 15)

{

full=1;

}

    else

{

full=empty=0;

}

}

}

 

 

 

SC_CTOR(sync_fifo)

{

SC_METHOD(read_write);

sensitive << clk.pos() << rst ;

sensitive << wptr ;

sensitive << rptr;

 

SC_METHOD(emp_ful);

sensitive << clk.pos() << rst ;

sensitive << wptr ;

sensitive << rptr ;

}

};

 

 

 

 

 

 

 

[kartikkg]

Hi Rashmi11,

 

sc_in < sc_uint<4> > wptr;

This is a declaration for an sc_in port. sc_in port =operator is private hence not accessible. Since its an in port you can only read values from it and not write to it. 

 

Regards Kartik

[Rashmi11]

Thank you Kartik.