DUT 2-dimensional memory read using $writememh is not working

SystemVerilog
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1

I’m stuck with an issue while reading a DUT 2-dimensional memory via backdoor using $writememh.
I’m trying to read a DUT 2-dimensional memory via backdoor using $writememh. But it’s not working and I’m getting junk data.

Syntax used: $writememh(“rtl_memory_hex.txt”,DUT.mem.MEMORY);

I even tried with the below syntax by giving start address & end address, but no use, still getting junk data instead of actual data.

Syntax used: $writememh(“rtl_memory_hex.txt”,DUT.mem.MEMORY,32’d0,32’d1023);

NOTE : In both of the above scenarios, I can see my actual data in dump. But in text file, I’m getting junk data.

NOTE: Here, MEMORY is a 2-dimensional array, and in each cell 136-bit data is written/stored and we are trying to read that 136-bit data, not address.

Whereas, when I try to read from a 1-dimensional array, it is working fine.

Syntax : $writememh(“rtl_memory_hex.txt”,DUT.mem.mem);

2

In reply to SV_UVM_Learner:

I am confused by your terminology. $writemem dumps a memory to a text file. What is it that you are reading and with what command?

What is the declaration of your memory?

Maybe try with an example of a much smaller 2-D memory where you can show us the entire contents and the text file that it dumps.

3

Hi Dave,

Thanks or your reply.
Yes, we are trying to read from DUT memory using $writememh and dumping that into a text file for later comparison.
Our AXI master VIP will send write transactions to DUT & all those transactions gets stored in this memory. As per UVM, we are doing comparison by sending data from both AXI WRITE & READ monitors to the UVM scoreboard. This is a level-1 check and it is already PASSING in our scenario.

For level-2 check, we want to read data from DUT memory and compare it with our write data from AXI VIP(by doing file comparisons). I’ve stored all data sending from AXI VIP into expected_file.txt. But when trying to read from memory using $writememh, I’m facing issue as mentioned.

declaration of our 2-dimesional memory is as follows :
reg [136:0] MEMORY [255:0][3:0];
NOTE : Here, 136, 255 & 3 are declared as parameters

declaration of our 1-dimesional memory is as follows :
reg [136:0] mem [1023:0];
NOTE : Here, 136, 1023 are declared as parameters

For 2-dimesional memory, I can see my actual data in the dump, but I’m always getting junk data into text file instead of actual data.
Syntax used: $writememh(“rtl_memory_hex.txt”,DUT.mem.MEMORY);

Whereas, when I try to read memory from a 1-dimensional array and dump into a text file, it is working fine.
Syntax : $writememh(“rtl_memory_hex.txt”,DUT.mem.mem);