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[/] [xulalx25soc/] [trunk/] [rtl/] [wbusixchar.v] - Blame information for rev 21

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///////////////////////////////////////////////////////////////////////////
//
// Filename:    wbusixchar.v
//
// Project:     XuLA2 board
//
// Purpose:     Supports a conversion from a six digit bus to a printable
//              ASCII character representing those six bits.  The encoding is
//              as follows:
//
//              0-9     ->      0-9
//              A-Z     ->      10-35
//              a-z     ->      36-61
//              @       ->      62
//              %       ->      63
//
//              Note that decoding is stateless, yet requires one clock.
//
//
// Creator:     Dan Gisselquist, Ph.D.
//              Gisselquist Technology, LLC
//
///////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2015, Gisselquist Technology, LLC
//
// This program is free software (firmware): you can redistribute it and/or
// modify it under the terms of  the GNU General Public License as published
// by the Free Software Foundation, either version 3 of the License, or (at
// your option) any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// License:     GPL, v3, as defined and found on www.gnu.org,
//              http://www.gnu.org/licenses/gpl.html
//
//
///////////////////////////////////////////////////////////////////////////
//
//
//
module  wbusixchar(i_clk, i_stb, i_bits, o_stb, o_char, o_busy, i_busy);
        input                   i_clk;
        input                   i_stb;
        input           [6:0]    i_bits;
        output  reg             o_stb;
        output  reg     [7:0]    o_char;
        output  wire            o_busy;
        input                   i_busy;
 
        initial o_char = 8'h00;
        always @(posedge i_clk)
                if ((i_stb)&&(~o_busy))
                begin
                        if (i_bits[6])
                                o_char <= 8'h0a;
                        else if (i_bits[5:0] <= 6'h09) // A digit, WORKS
                                o_char <= "0" + { 4'h0, i_bits[3:0] };
                        else if (i_bits[5:0] <= 6'd35) // Upper case
                                o_char <= "A" + { 2'h0, i_bits[5:0] } - 8'd10; // -'A'+10
                        else if (i_bits[5:0] <= 6'd61)
                                o_char <= "a" + { 2'h0, i_bits[5:0] } - 8'd36;// -'a'+(10+26)
                        else if (i_bits[5:0] == 6'd62) // An '@' sign
                                o_char <= 8'h40;
                        else // if (i_char == 6'h63) // A '%' sign
                                o_char <= 8'h25;
                end
 
        always @(posedge i_clk)
                if ((o_stb)&&(~i_busy))
                        o_stb <= 1'b0;
                else if ((i_stb)&&(~o_stb))
                        o_stb <= 1'b1;
 
        assign  o_busy = o_stb;
 
endmodule
 

Line No.	Rev	Author	Line
1	2	dgisselq	`///////////////////////////////////////////////////////////////////////////`
2			`//`
3			`// Filename: wbusixchar.v`
4			`//`
5			`// Project: XuLA2 board`
6			`//`
7			`// Purpose: Supports a conversion from a six digit bus to a printable`
8			`// ASCII character representing those six bits. The encoding is`
9			`// as follows:`
10			`//`
11			`// 0-9 -> 0-9`
12			`// A-Z -> 10-35`
13			`// a-z -> 36-61`
14			`// @ -> 62`
15			`// % -> 63`
16			`//`
17			`// Note that decoding is stateless, yet requires one clock.`
18			`//`
19			`//`
20			`// Creator: Dan Gisselquist, Ph.D.`
21			`// Gisselquist Technology, LLC`
22			`//`
23			`///////////////////////////////////////////////////////////////////////////`
24			`//`
25			`// Copyright (C) 2015, Gisselquist Technology, LLC`
26			`//`
27			`// This program is free software (firmware): you can redistribute it and/or`
28			`// modify it under the terms of the GNU General Public License as published`
29			`// by the Free Software Foundation, either version 3 of the License, or (at`
30			`// your option) any later version.`
31			`//`
32			`// This program is distributed in the hope that it will be useful, but WITHOUT`
33			`// ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY or`
34			`// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License`
35			`// for more details.`
36			`//`
37			`// License: GPL, v3, as defined and found on www.gnu.org,`
38			`// http://www.gnu.org/licenses/gpl.html`
39			`//`
40			`//`
41			`///////////////////////////////////////////////////////////////////////////`
42			`//`
43			`//`
44			`//`
45			`module wbusixchar(i_clk, i_stb, i_bits, o_stb, o_char, o_busy, i_busy);`
46			`input i_clk;`
47			`input i_stb;`
48			`input [6:0] i_bits;`
49			`output reg o_stb;`
50			`output reg [7:0] o_char;`
51			`output wire o_busy;`
52			`input i_busy;`
53
54	9	dgisselq	`initial o_char = 8'h00;`
55	2	dgisselq	`always @(posedge i_clk)`
56			`if ((i_stb)&&(~o_busy))`
57			`begin`
58			`if (i_bits[6])`
59			`o_char <= 8'h0a;`
60			`else if (i_bits[5:0] <= 6'h09) // A digit, WORKS`
61			`o_char <= "0" + { 4'h0, i_bits[3:0] };`
62			`else if (i_bits[5:0] <= 6'd35) // Upper case`
63			`o_char <= "A" + { 2'h0, i_bits[5:0] } - 8'd10; // -'A'+10`
64			`else if (i_bits[5:0] <= 6'd61)`
65			`o_char <= "a" + { 2'h0, i_bits[5:0] } - 8'd36;// -'a'+(10+26)`
66			`else if (i_bits[5:0] == 6'd62) // An '@' sign`
67			`o_char <= 8'h40;`
68			`else // if (i_char == 6'h63) // A '%' sign`
69			`o_char <= 8'h25;`
70			`end`
71
72			`always @(posedge i_clk)`
73			`if ((o_stb)&&(~i_busy))`
74			`o_stb <= 1'b0;`
75			`else if ((i_stb)&&(~o_stb))`
76			`o_stb <= 1'b1;`
77
78			`assign o_busy = o_stb;`
79
80			`endmodule`
81

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[/] [xulalx25soc/] [trunk/] [rtl/] [wbusixchar.v] - Blame information for rev 21