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Forum: FPGA, VHDL & Verilog sdram controller read/write need help


von ladybird (Guest)


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hello all. please i need some help
i would like to display two images on a vga screen. and i'm using the 
sdram to temporarely save frames before display. when i was using only 
one image i didn't have any problem i had two write fifo and two read 
fifo. but when i attempt to write/read another image means i added two 
other FiFOs for the write and two other read Fifos for the read, i get a 
mess on the vga display, knowing that i added a display module to decide 
where to display the image since i divided the screen into 2. below is 
an excerpt of the sdram control code
1
if (WR1_LOAD)
2
        rWR1_ADDR    <= WR1_ADDR;
3
      else
4
    if (mWR_DONE&&WR_MASK[0])
5
        begin
6
            if (rWR1_ADDR<WR1_MAX_ADDR-WR1_LENGTH)
7
                rWR1_ADDR    <= rWR1_ADDR+WR1_LENGTH;
8
            else
9
                rWR1_ADDR    <= WR1_ADDR;
10
        end
11
        //    Write Side 2
12
    if (WR2_LOAD)
13
        rWR2_ADDR    <= WR2_ADDR;
14
        else if (mWR_DONE&&WR_MASK[1])
15
        begin
16
            if (rWR2_ADDR<WR2_MAX_ADDR-WR2_LENGTH)
17
                rWR2_ADDR    <=    rWR2_ADDR+WR2_LENGTH;
18
            else
19
                rWR2_ADDR    <=    WR2_ADDR;
20
        end
21
//    Write Side 3
22
    if (WR3_LOAD)
23
        rWR3_ADDR    <= WR3_ADDR;
24
      else
25
    if (mWR_DONE&&WR_MASK[2])
26
        begin
27
            if (rWR3_ADDR<WR3_MAX_ADDR-WR3_LENGTH)
28
                rWR3_ADDR    <= rWR3_ADDR+WR3_LENGTH;
29
            else
30
                rWR3_ADDR    <= WR3_ADDR;
31
        end
32
        //    Write Side 4
33
    if (WR4_LOAD)
34
        rWR4_ADDR    <= WR4_ADDR;
35
        else if (mWR_DONE&&WR_MASK[3])
36
        begin
37
            if (rWR4_ADDR<WR4_MAX_ADDR-WR4_LENGTH)
38
                rWR4_ADDR    <=    rWR4_ADDR+WR4_LENGTH;
39
            else
40
                rWR4_ADDR    <=    WR4_ADDR;
41
        end
42
    //    Read Side 1
43
      if (RD1_LOAD)
44
            rRD1_ADDR    <= RD1_ADDR;
45
        else if (mRD_DONE&&RD_MASK[0])
46
        begin
47
            if (rRD1_ADDR<RD1_MAX_ADDR-RD1_LENGTH)
48
                rRD1_ADDR    <=    rRD1_ADDR+RD1_LENGTH;
49
            else
50
                rRD1_ADDR    <=    RD1_ADDR;
51
        end
52
        //    Read Side 2
53
        if (mRD_DONE&&RD_MASK[1])
54
        begin
55
            if (rRD2_ADDR<RD2_MAX_ADDR-RD2_LENGTH)
56
                rRD2_ADDR    <=    rRD2_ADDR+RD2_LENGTH;
57
            else
58
                rRD2_ADDR    <=    RD2_ADDR;
59
        end
60
    //    Read Side 3
61
      if (RD3_LOAD)
62
            rRD3_ADDR    <= RD3_ADDR;
63
        else if (mRD_DONE&&RD_MASK[2])
64
        begin
65
            if (rRD3_ADDR<RD3_MAX_ADDR-RD3_LENGTH)
66
                rRD3_ADDR    <=    rRD3_ADDR+RD3_LENGTH;
67
            else
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                rRD3_ADDR    <=    RD3_ADDR;
69
        end
70
        //    Read Side 4
71
        if (mRD_DONE&&RD_MASK[3])
72
        begin
73
            if (rRD4_ADDR<RD4_MAX_ADDR-RD4_LENGTH)
74
                rRD4_ADDR    <=    rRD4_ADDR+RD4_LENGTH;
75
            else
76
                rRD4_ADDR    <=    RD4_ADDR;
77
        end
78
    end
in  the main program the sdram is mapped this way
1
    Sdram_Control    u7    (    //    HOST Side                       
2
                                .RESET_N(KEY[0]),
3
                                .CLK(sdram_ctrl_clk),
4
5
    //                            //    FIFO Write Side 1
6
                                .WR1_DATA({1'b0,sCCD_G[11:7],sCCD_B[11:2]}),
7
                                .WR1(sCCD_DVAL),
8
                                .WR1_ADDR(0),
9
                               .WR1_MAX_ADDR(640*480/2),
10
                               .WR1_LENGTH(8'h50),
11
                                .WR1_LOAD(!DLY_RST_0),
12
                                .WR1_CLK(PIXCLK),
13
    //
14
    //                            //    FIFO Write Side 2
15
                                .WR2_DATA({1'b0,sCCD_G[6:2],sCCD_R[11:2]}),
16
                                .WR2(sCCD_DVAL),
17
                                .WR2_ADDR(23'h25800),
18
19
                               .WR2_MAX_ADDR(23'h25800+640*480/2),
20
                                .WR2_LENGTH(8'h50),
21
                                .WR2_LOAD(!DLY_RST_0),
22
                                .WR2_CLK(PIXCLK),
23
24
    //                                                       
25
    //                            //    FIFO Write Side 3
26
                                .WR3_DATA(data_test1),
27
                                .WR3(valid),
28
                                .WR3_ADDR(23'h60000),
29
                               .WR3_MAX_ADDR(23'h85800),
30
                               .WR3_LENGTH(8'h50),
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                                .WR3_LOAD(!DLY_RST_0),
32
                                .WR3_CLK(PIXCLK),
33
    //
34
    //                            //    FIFO Write Side 3
35
                                .WR4_DATA(data_test2),
36
                                .WR4(valid),
37
                                .WR4_ADDR(23'h90000),
38
                               .WR4_MAX_ADDR(23'h90000+640*480/2),
39
                                .WR4_LENGTH(8'h50),
40
                                .WR4_LOAD(!DLY_RST_0),
41
                                .WR4_CLK(PIXCLK),
42
43
                                //    FIFO Read Side 1
44
                               .RD1_DATA(Read_DATA1),
45
                                .RD1(vga_read),
46
                                .RD1_ADDR(0),
47
                               .RD1_MAX_ADDR(640*480/2),
48
                                .RD1_LENGTH(8'h50),
49
                                .RD1_LOAD(!DLY_RST_0),
50
                                .RD1_CLK(~VGA_CTRL_CLK),
51
    //                           
52
    //                            //    FIFO Read Side 2
53
                                .RD2_DATA(Read_DATA2),
54
                                .RD2(vga_read),
55
                                .RD2_ADDR(23'h25800),
56
                                .RD2_MAX_ADDR(23'h25800+640*480/2),
57
                                .RD2_LENGTH(8'h50),
58
                                .RD2_LOAD(!DLY_RST_0),
59
                                .RD2_CLK(~VGA_CTRL_CLK),
60
    ////                           
61
    //////                            //    FIFO Read Side 1
62
                                .RD3_DATA(Read_DATA3),
63
                                .RD3(vga_read),
64
                              .RD3_ADDR(23'h60000),
65
                              .RD3_MAX_ADDR(23'h85800),
66
                               .RD3_LENGTH(8'h50),
67
                                .RD3_LOAD(!DLY_RST_0),
68
                                .RD3_CLK(~VGA_CTRL_CLK),
69
    ////                           
70
    //                            //    FIFO Read Side 2
71
                               .RD4_DATA(Read_DATA4),
72
                              .RD4(vga_read),                       
73
                               .RD4_ADDR(23'h90000),
74
                                .RD4_MAX_ADDR(23'h90000+640*480/2),
75
                            .RD4_LENGTH(8'h50),
76
                              .RD4_LOAD(!DLY_RST_0),
77
                               .RD4_CLK(~VGA_CTRL_CLK),
78
                             
79
                                //    SDRAM Side
80
                                .SA(DRAM_ADDR),
81
                                .BA(DRAM_BA),
82
                                .CS_N(DRAM_CS_N),
83
                                .CKE(DRAM_CKE),
84
                                .RAS_N(DRAM_RAS_N),
85
                                .CAS_N(DRAM_CAS_N),
86
                                .WE_N(DRAM_WE_N),
87
                                .DQ(DRAM_DQ),
88
                                .DQM(DRAM_DQM)
89
                            );
i've a DE2-115 Board and i'm using quartus 10.0
Thank u

von dave (Guest)


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Hi Ladybird,

do u already solved  your problem?
I also need to implement a controller of the sdram, but I have problems
to run it oin the board. May be we can change some ideas.

cheers, Dave

von Wayne Gretzky (Guest)


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Maybe you sit done and write some block diagram first to show people 
what you want to knwo and what you did? Nobody want's to guess it from a 
non working code.

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