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Line 29... |
//
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//
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// *Author(s):
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// *Author(s):
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// - Olivier Girard, olgirard@gmail.com
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// - Olivier Girard, olgirard@gmail.com
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//
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//
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//----------------------------------------------------------------------------
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//----------------------------------------------------------------------------
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// $Rev: 54 $
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// $Rev: 61 $
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// $LastChangedBy: olivier.girard $
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// $LastChangedBy: olivier.girard $
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// $LastChangedDate: 2010-01-27 19:25:43 +0100 (Wed, 27 Jan 2010) $
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// $LastChangedDate: 2010-02-03 23:14:03 +0100 (Wed, 03 Feb 2010) $
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//----------------------------------------------------------------------------
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//----------------------------------------------------------------------------
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`include "timescale.v"
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`include "timescale.v"
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`include "openMSP430_defines.v"
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`include "openMSP430_defines.v"
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module omsp_frontend (
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module omsp_frontend (
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//-----------------------------------------
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//-----------------------------------------
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// Program counter
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// Program counter
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reg [15:0] pc;
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reg [15:0] pc;
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// Detect if PC needs to be incremented
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wire pc_inc = (~pc_sw_wr & fetch) & ~(i_state==I_IRQ_FETCH) & ~(i_state==I_IRQ_DONE);
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// Mux between software update and old PC
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wire [15:0] pc_sel = pc_sw_wr ? pc_sw :
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(i_state==I_IRQ_FETCH) ? irq_addr :
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(i_state==I_IRQ_DONE) ? mdb_in : pc;
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// Compute next PC value
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// Compute next PC value
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wire [15:0] pc_nxt = pc_sel + {14'h0000, pc_inc, 1'b0};
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wire [15:0] pc_incr = pc + {14'h0000, fetch, 1'b0};
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wire [15:0] pc_nxt = pc_sw_wr ? pc_sw :
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(i_state==I_IRQ_FETCH) ? irq_addr :
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(i_state==I_IRQ_DONE) ? mdb_in : pc_incr;
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always @(posedge mclk or posedge puc)
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always @(posedge mclk or posedge puc)
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if (puc) pc <= 16'h0000;
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if (puc) pc <= 16'h0000;
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else pc <= pc_nxt;
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else pc <= pc_nxt;
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