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Altera_Forum
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10 years ago

Vector sizes for Qsys generated HPS memory pins

I'm using SoCKit rev C, SD Card image 14.0 from Rocketboards, Quartus II 14.0.

All the reference designs I've seen have the following in the Qsys generated port list of the top level soc_system.v :

output wire [14:0] memory_mem_a, // memory.mem_a

output wire [2:0] memory_mem_ba, // .mem_ba

output wire memory_mem_ck, // .mem_ck

output wire memory_mem_ck_n, // .mem_ck_n

output wire memory_mem_cke, // .mem_cke

output wire memory_mem_cs_n, // .mem_cs_n

output wire memory_mem_ras_n, // .mem_ras_n

output wire memory_mem_cas_n, // .mem_cas_n

output wire memory_mem_we_n, // .mem_we_n

output wire memory_mem_reset_n, // .mem_reset_n

inout wire [31:0] memory_mem_dq, // .mem_dq

inout wire [3:0] memory_mem_dqs, // .mem_dqs

inout wire [3:0] memory_mem_dqs_n, // .mem_dqs_n

output wire memory_mem_odt, // .mem_odt

output wire [3:0] memory_mem_dm, // .mem_dm

input wire memory_oct_rzqin,

The above vector sizes correspond to number of pins that connect to the HPS-side DDR3 device on the SoCKit board, as spec'd in the SoCKit User Manual. For example, Sockit has HPS_DDR3_DQ[31:0] connections as the data bus going out to the HPS-side DDR3.

In my design, Qsys generated the following:

output wire [12:0] memory_mem_a, // memory.mem_a

output wire [2:0] memory_mem_ba, // .mem_ba

output wire memory_mem_ck, // .mem_ck

output wire memory_mem_ck_n, // .mem_ck_n

output wire memory_mem_cke, // .mem_cke

output wire memory_mem_cs_n, // .mem_cs_n

output wire memory_mem_ras_n, // .mem_ras_n

output wire memory_mem_cas_n, // .mem_cas_n

output wire memory_mem_we_n, // .mem_we_n

output wire memory_mem_reset_n, // .mem_reset_n

inout wire [7:0] memory_mem_dq, // .mem_dq

inout wire memory_mem_dqs, // .mem_dqs

inout wire memory_mem_dqs_n, // .mem_dqs_n

output wire memory_mem_odt, // .mem_odt

output wire memory_mem_dm, // .mem_dm

input wire memory_oct_rzqin, // .oct_rzqin

Question:

What would make my Qsys generated vector sizes different from every other design I've seen?

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Looks like you setup the memory to be only 8-bits wide and have two fewer row address bits than the design at the top uses. That means the span of the memory you setup is 16 times less than the one at the top.