FreeCalypso > hg > fc-pcm-if

annotate fpga/mcsi-rx/clk_edge.v @ 2:a4918a161d2e

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sw: starting with libserial, copied from fc-sim-sniff
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 11 Oct 2024 22:37:11 +0000
parents b3190839cce3
children
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1 /*
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2 * This Verilog module captures the logic that detects falling edges of
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3 * MCSI_CLK: it is the edge on which we have to sample data and frame sync.
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4 */
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6 module clk_edge (IntClk, MCSI_CLK_sync, MCSI_CLK_negedge);
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8 input IntClk;
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9 input MCSI_CLK_sync;
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10 output MCSI_CLK_negedge;
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12 reg prev_state;
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14 always @(posedge IntClk)
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15 prev_state <= MCSI_CLK_sync;
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17 assign MCSI_CLK_negedge = !MCSI_CLK_sync && prev_state;
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19 endmodule