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Error using SOPC builder - "Custom SDRAM" with 8-bits gives error with Signal "az_be_n"

Started by Unknown October 18, 2007
I'm trying to make a SDRAM controller with SOPC builder, but when I
change the data width to 8bits I get the following error..

Warning: Signal "az_be_n" of type "byteenable_n" and width 1 must have
width of 2, 4, 8, 16, 32, 64, 128.

I'm trying to make the system for a 64Mb SDR SDRAM, Micron
MT48LC8M8A2P-75.

Even when I select the Alliance AS4LC2M8S0-10 chip it does the same
thing. So I'm guessing it has to do with a width of 8 bits.

Thank you,
Eric

On Oct 18, 12:39 pm, sendt...@gmail.com wrote:
> I'm trying to make a SDRAM controller with SOPC builder, but when I > change the data width to 8bits I get the following error.. > > Warning: Signal "az_be_n" of type "byteenable_n" and width 1 must have > width of 2, 4, 8, 16, 32, 64, 128. > > I'm trying to make the system for a 64Mb SDR SDRAM, Micron > MT48LC8M8A2P-75. > > Even when I select the Alliance AS4LC2M8S0-10 chip it does the same > thing. So I'm guessing it has to do with a width of 8 bits. > > Thank you, > Eric
If this is your own component that you're trying to make up in SOPC Builder, then I think the problem has to do with that the 'byteenable_n' SOPC input is supposed to be a vector. When you have an 8 bit datapath, there will only be one byte enable input which I'm guessing you have defined as a std_logic and not a std_logic_vector. Wrong: az_be_n: std_logic -- Maps to SOPC's byteenable_n Correct: az_be_n: std_logic_vector(0 downto 0); -- Maps to SOPC's byteenable_n I'm not totally sure, I haven't used SOPC Builder in a while but I seem to recall an issue like this. KJ