DE0-Nano Accelerometer code help (almost there)

Question

Can anyone spot the problem with my VHDL-code please? I pasted it at the pastebin because it was over 1000 lines:rolleyes:  http://pastebin.com/draraqr7  Line 384 and 480 -- data1(7) &lt;= I2C_sdat; -- SOMETHING WRONG HERE: CANT RESOLVE MULTIPLE CONSTANT DRIVERS FRO NET "q" (line 54)  This was the original verilog code: // ADXL clock= 500,000samples of 50Mhz/100Hz
// ADXL address= 0x1D/11101 (alt address pin grounded)
module ADXL_Read(clk_50, I2C_sclk, I2C_sdat, key0, key1, clk_st, data1);
input clk_50;
output I2C_sclk;
output data1;
inout I2C_sdat;
input key0; //Trigger0 to reset
input key1; //Trigger1 to begin
output clk_st;
reg  a;
reg  b;
reg clk; //Clk for slave
reg clk_signaltap; //Clk for signaltap2
reg q; //Register for Trigger
reg  step;
reg  sl_ad = 7'b0011101; // Slave Address
reg  reg_ad = 8'h2D; // Register Address
reg  data1; // Databyte#1
reg sclk;
reg sdat;
initial begin
step = 0;
q = 0;
end
always @(posedge clk_50)
begin
if(a == 1000000) //Clock for Slave with sample 2a
begin
clk = ~clk;
a = 1;
end
else
a = a + 1;
//Signaltap begin
if(b == 500000) //Clock for Signaltap2
begin
clk_signaltap = ~clk_signaltap;
b = 1;
end
else
b = b + 1;
end
//Signaltap end
always @(posedge clk_50) //Trigger Condition
case({!key1, !key0}) //Active low
2'b00 : q &lt;= q;
2'b10 : q &lt;= 1; //Set
2'b01 : q &lt;= 0; //Reset
endcase
always @(posedge clk)
begin
if (q == 1)
begin
case(step)
//Initial
0: begin sclk = 1; sdat = 1; step = 1; end
//1.Start
1: begin sclk = 1; sdat = 0; step = 2; end
2: begin sclk = 0; sdat = 0; step = 3; end
//2.Slave add
3: begin sclk = 0; sdat = sl_ad; step = 4; end
4: begin sclk = 1; sdat = sl_ad; step = 5; end
5: begin sclk = 0; sdat = sl_ad; step = 6; end
6: begin sclk = 1; sdat = sl_ad; step = 7; end
7: begin sclk = 0; sdat = sl_ad; step = 8; end
8: begin sclk = 1; sdat = sl_ad; step = 9; end
9: begin sclk = 0; sdat = sl_ad; step = 10; end
10: begin sclk =1; sdat = sl_ad; step = 11; end
11: begin sclk = 0; sdat = sl_ad; step = 12; end
12: begin sclk = 1; sdat = sl_ad; step = 13; end
13: begin sclk = 0; sdat = sl_ad; step = 14; end
14: begin sclk = 1; sdat = sl_ad; step = 15; end
15: begin sclk = 0; sdat = sl_ad; step = 16; end
16: begin sclk = 1; sdat = sl_ad; step = 17; end
//3.sdat = 0
17: begin sclk = 0; sdat = 0; step = 18; end
18: begin sclk = 1; sdat = 0; step = 19; end
//4.Acknowledge
19: begin sclk = 0; sdat = 1'bz; step = 20; end
20: begin sclk = 1; sdat = 1'bz; if (I2C_sdat == 1) step = 20; else step = 21; end
//5.Reg add
21: begin sclk = 0; sdat = reg_ad; step = 22; end //7
22: begin sclk = 1; sdat = reg_ad; step = 23; end
23: begin sclk = 0; sdat = reg_ad; step = 24; end //6
24: begin sclk = 1; sdat = reg_ad; step = 25; end
25: begin sclk = 0; sdat = reg_ad; step = 26; end //5
26: begin sclk = 1; sdat = reg_ad; step = 27; end
27: begin sclk = 0; sdat = reg_ad; step = 28; end //4
28: begin sclk = 1; sdat = reg_ad; step = 29; end
29: begin sclk = 0; sdat = reg_ad; step = 30; end //3
30: begin sclk = 1; sdat = reg_ad; step = 31; end
31: begin sclk = 0; sdat = reg_ad; step = 32; end //2
32: begin sclk = 1; sdat = reg_ad; step = 33; end
33: begin sclk = 0; sdat = reg_ad; step = 34; end //1
34: begin sclk = 1; sdat = reg_ad; step = 35; end
35: begin sclk = 0; sdat = reg_ad; step = 36; end //0
36: begin sclk = 1; sdat = reg_ad; step = 37; end
//6.Acknowledge
37: begin sclk = 0; sdat = 1'bz; step = 38; end
38: begin sclk = 1; sdat = 1'bz; if (I2C_sdat == 1) step = 38; else step = 39; end
//7.Start
39: begin sclk = 0; sdat = 0; step = 40; end //sclk= 0, sdat= 0
40: begin sclk = 1; sdat = 1; step = 41; end //sclk= 1, sdat= 1
41: begin sclk = 1; sdat = 0; step = 42; end //sclk= 1, sdat= 0
42: begin sclk = 0; sdat = 0; step = 45; end //sclk= 0, sdat= 0 ---------------
//8.Slave Add
45: begin sclk = 0; sdat = sl_ad; step = 46; end //6
46: begin sclk = 1; sdat = sl_ad; step = 47; end
47: begin sclk = 0; sdat = sl_ad; step = 48; end //5
48: begin sclk = 1; sdat = sl_ad; step = 49; end
49: begin sclk = 0; sdat = sl_ad; step = 50; end //4
50: begin sclk = 1; sdat = sl_ad; step = 51; end
51: begin sclk = 0; sdat = sl_ad; step = 52; end //3
52: begin sclk = 1; sdat = sl_ad; step = 53; end
53: begin sclk = 0; sdat = sl_ad; step = 54; end //2
54: begin sclk = 1; sdat = sl_ad; step = 55; end
55: begin sclk = 0; sdat = sl_ad; step = 56; end //1
56: begin sclk = 1; sdat = sl_ad; step = 57; end
57: begin sclk = 0; sdat = sl_ad; step = 58; end //0
58: begin sclk = 1; sdat = sl_ad; step = 59; end
//9.sdat = 1
59: begin sclk = 0; sdat = 1; step = 60; end
60: begin sclk = 1; sdat = 1; step = 61; end
//10.Acknowledge
61: begin sclk = 0; sdat = 1'bz; step = 62; end
62: begin sclk = 1; sdat = 1'bz; if (I2C_sdat == 1) step = 62; else step = 63; end
//11.Databyte#1
63: begin sclk = 0; sdat = 1'bz; step = 64; end //Databyte#1 bit 7
64: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 65; end
65: begin sclk = 0; sdat = 1'bz; step = 66; end //6
66: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 67; end
67: begin sclk = 0; sdat = 1'bz; step = 68; end //5
68: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 69; end
69: begin sclk = 0; sdat = 1'bz; step = 70; end //4
70: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 71; end
71: begin sclk = 0; sdat = 1'bz; step = 72; end //3
72: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 73; end
73: begin sclk = 0; sdat = 1'bz; step = 74; end //2
74: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 75; end
75: begin sclk = 0; sdat = 1'bz; step = 76; end //1
76: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 77; end
77: begin sclk = 0; sdat = 1'bz; step = 78; end //0
78: begin sclk = 1; sdat = 1'bz; data1 = I2C_sdat; step = 79; end
//12.Acknowledge
79: begin sclk = 0; sdat = 1'bz; step = 80; end
80: begin sclk = 1; sdat = 1'bz; if (I2C_sdat == 1) step = 80; else step = 81; end
//13.Stop
81: begin sclk = 1; sdat = 0; step = 82; end //sclk= 1, sdat= 0
82: begin sclk = 1; sdat = 1; step = 83; end //sclk= 1, sdat= 1
83: begin sclk = 1; sdat = 1; end
endcase
end
end
assign I2C_sclk = sclk;
assign I2C_sdat = sdat;
assign clk_st = clk_signaltap;
endmodule

altera_forum · Answer

Your two line codes after the "begin" (lines 52 and 53) don't define initial conditions, as I guess is doing the "initial" block in the Verilog code, but is permanently assigning the values "00000000000" and '0' to step and q. You may want to put those initialisations in a reset part in each process, or just define the initial value when you declare the signal. This, for example:   SIGNAL q             : STD_LOGIC := '0';
   SIGNAL step          : STD_LOGIC_VECTOR(10 DOWNTO 0) := (others =&gt; '0');

altera_forum · Answer

Don't understand what you mean with -- SOMETHING WRONG HERE and why the final signal assignments are commented.

Verilog Initial block is exactly represented by the initializers Daixiwen suggested. Initialization to 0 is only required for simulation purposes, hardware registers are initially zeroed without an explicite initializer.

altera_forum · Answer

TO_BE_DONE

altera_forum · Answer

Hi ozshay:

I've put the code on my website, so you can download it.

Download VHDL project (code, report, powerpoint):

http://w3senteret.com/vhdl/nano/vhdl_prosjekt_2012.php

..or..

http://translate.google.com/translate?sl=no&tl=en&js=n&prev=_t&hl=no&ie=utf-8&layout=2&eotf=1&u=http%3a%2f%2fw3senteret.com%2fvhdl%2fnano%2fvhdl_prosjekt_2012.php&act=url

altera_forum · Answer

Hi I am working with De0-Nano, you can help me with VHDL code for accelerometer? you have it available for me send?   Thank you Nouara

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DE0-Nano Accelerometer code help (almost there)

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