annotate fpga/sniffer-basic/reset_detect.v @ 45:b0524d1dc6ef

simtrace3-sniff-dec: implement command decoding
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 31 Aug 2023 09:32:48 +0000
parents 7db5fd6646df
children
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1 /*
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2 * This Verilog module captures the logic that detects SIM_RST transitions
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3 * in either direction.
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4 */
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6 module reset_detect (IntClk, SIM_RST_sync, SIM_RST_toggle);
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8 input IntClk;
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9 input SIM_RST_sync;
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10 output SIM_RST_toggle;
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12 reg prev_state;
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14 always @(posedge IntClk)
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15 prev_state <= SIM_RST_sync;
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17 assign SIM_RST_toggle = SIM_RST_sync != prev_state;
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18
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19 endmodule