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I have a design in AHDL for a keyboard scanner and I'm trying to convert this to Verilog.
The AHDL code is in the enclosed ZIP "kbd.zip". The Verilog code is shown hereunder. The line "assign lresult = (sensecount == i) && sense[7 - i];" gives an error that lresult is driven by multiple gates. Anyone an idea how I can solve that? Further remarks about the Verilog code also welcome. Thanks module kbd (sync,advance,mosi,eesel_n,sense,result,drv) ; // Input Port Declarations input sync; input advance; input mosi; input eesel_n; input [7 : 0] sense; // Output Port Declarations output result; output [15 : 0] drv; // Internal variables reg [15 : 0] drvcount; reg [7 : 0] sensecount; wire [15 : 0] ldrv; wire lresult; genvar i; always @(posedge sync) begin if (!eesel_n) drvcount <= 0; else drvcount <= drvcount + 1; end for (i=0;i<15;i=i+1) begin assign ldrv[i] = (drvcount == i); end assign drv = !ldrv; always @(negedge advance or posedge sync) begin if(sync) sensecount <= 0; else sensecount <= sensecount + 1; end for (i=0;i<7;i=i+1) begin assign lresult = (sensecount == i) && sense[7 - i]; end assign result = (eesel_n)? lresult : 1'bZ; // add design description here endmoduleLink Copied
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Shouldnt lresult be a 6 bit vector. Otherwise lresult is being driven by each iteration of the for loop.
If you didn't know, xilinx ise used to ship with an ahdl to vhdl/verilog translater. Xhdl I think.- Mark as New
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Why do you want to convert when AHDL is such a cool language. From Assembly one can move to C++ and discover ease of coding, but from AHDL it is impossible to move out to high level languages. Thanks Intel for continuing to support AHDL.
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AHDL does an implied or of multiple assignments to the same variable.
So line 47 in kbd.tdf translates to something like this (I don't do Verilog well)
assign lresult = ((sensecount == 0) && sense) || ((sensecount == 1) && sense) || ((sensecount == 2) && sense) || ((sensecount == 3) && sense)
|| ((sensecount == 4) && sense) || ((sensecount == 5) && sense) || ((sensecount == 6) && sense) || ((sensecount == 7) && sense);
But I guess that a simple indexing works as well:
assign lresult = sense;

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