FreeCalypso > hg > fc-pcm-if
annotate fpga/mcsi-rx/clk_edge.v @ 11:e93a11f44e6f
fc-mcsi-rxtx: implement basic Tx
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Mon, 28 Oct 2024 06:34:42 +0000 |
parents | b3190839cce3 |
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rev | line source |
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b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 /* |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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2 * This Verilog module captures the logic that detects falling edges of |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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3 * MCSI_CLK: it is the edge on which we have to sample data and frame sync. |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
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changeset
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4 */ |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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5 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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6 module clk_edge (IntClk, MCSI_CLK_sync, MCSI_CLK_negedge); |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
7 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
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changeset
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8 input IntClk; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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9 input MCSI_CLK_sync; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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10 output MCSI_CLK_negedge; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
11 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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12 reg prev_state; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
13 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
14 always @(posedge IntClk) |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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15 prev_state <= MCSI_CLK_sync; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
16 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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17 assign MCSI_CLK_negedge = !MCSI_CLK_sync && prev_state; |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
18 |
b3190839cce3
first FPGA version, MCSI Rx only
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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19 endmodule |