FreeCalypso > hg > fc-sim-sniff
annotate fpga/sniffer-basic/clk_edge.v @ 34:c2fc75655937
doc/PPS-catcher-FSM: it has been implemented
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 29 Aug 2023 22:58:26 +0000 |
parents | 7db5fd6646df |
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7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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1 /* |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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2 * This Verilog module captures the logic that detects rising edges of SIM_CLK |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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3 * for the purpose of counting them. |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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4 */ |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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5 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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6 module clk_edge (IntClk, SIM_CLK_sync, SIM_CLK_edge); |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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7 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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8 input IntClk; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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9 input SIM_CLK_sync; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 output SIM_CLK_edge; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
parents:
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11 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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12 reg prev_state; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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13 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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14 always @(posedge IntClk) |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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15 prev_state <= SIM_CLK_sync; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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16 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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17 assign SIM_CLK_edge = SIM_CLK_sync && !prev_state; |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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diff
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18 |
7db5fd6646df
fpga/sniffer-basic: initial version
Mychaela Falconia <falcon@freecalypso.org>
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19 endmodule |