usage of pack & unpack in URM

I am not sure I would advocate using URM pack/unpack because you have to know a lot about what is going on. In OVM the packer has functions to pack various object types and the automation is there. You will see from this example that it is pretty ugly to do this in URM. Of course you can make your own convenience functions to simplify this greatly. module test; `include "urm.svh" class mydata extends urm_object; int sz; byte payload[]; function void resize(int size); sz = size; payload = new[sz](payload); endfunction function void do_pack (ref bit bitstream[], input urm_packer packer); //Used to size the bitstream array if(packer.nopack) begin packer.count+= (payload.size()*8) + $bits(sz); return; end for(int i=$bits(sz)-1; i>=0; --i) begin bitstream[packer.count] = sz>>i; packer.count++; end for(int j=0; j=0; --i) begin bitstream[packer.count] = payload[j]>>i; packer.count++; end endfunction function void do_unpack (ref bit bitstream[], input urm_packer packer); sz = 0; for(int i=0; i<$bits(sz); ++i) begin sz = (sz<<1) + bitstream[packer.count]; packer.count++; end resize(sz); for(int j=0; j=0; --i) begin payload[j] = (payload[j]<<1) + bitstream[packer.count]; packer.count++; end end endfunction `urm_object_utils_begin(mydata) `urm_field_int(sz, DEFAULT) `urm_field_array_int(payload, DEFAULT) `urm_object_utils_end endclass mydata md = new; mydata md2 = new; bit bits[]; initial begin md.set_name("md"); md2.set_name("md2"); md.resize(10); for(int i=0; i<10; ++i) md.payload[i] = i*i; void'(md.pack(bits)); void'(md2.unpack(bits)); md.print(); md2.print(); end endmodule Tim