Suddenly, I am made to look into some verilog testbench code which heavily uses $readmemh, and $writememh. I understood that it basically read to memory and write to memory. I will be happy if you can point to some resources related to those routines. PS: I searched in google for no success. (I am very ... very new to Verilog)
+3
A:
Hi,
I agree its not too easy to find something about readmem/writemem. You can find a little bit here: http://fullchipdesign.com/index_files/readmemh.htm
Anyway there is not too much to say about these functions, the syntax is:
$readmem[hb]("File",ArrayName,StartAddr,EndAddr)
$writemem[hb]("File",ArrayName,StartAddr,EndAddr)
Verilog is very picky about the file format, the number of bit in the text file have to match the number of bits in the array.
I recommend you play around a little bit by defining an array, filling it up with data write it out with writememh/writememb and print it out afterwards.
Something like this should get you started (not tried out!).
integer i;
reg [7:0] memory [0:15]; // 8 bit memory with 16 entries
initial begin
for (i=0; i<16; i++) begin
memory = i;
end
$writememb("memory_binary.txt", memory);
$writememh("memory_hex.txt", memory);
end
Cheers!
danielpoe
2009-03-10 11:45:12