annotate fpga/mcsi-rx/clk_check.v @ 1:b3190839cce3

first FPGA version, MCSI Rx only
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 11 Oct 2024 21:11:24 +0000
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b3190839cce3 first FPGA version, MCSI Rx only
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1 /*
b3190839cce3 first FPGA version, MCSI Rx only
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2 * The logic implemented in this module detects if MCSI_CLK is running or not,
b3190839cce3 first FPGA version, MCSI Rx only
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3 * for the purpose of visual indication on a LED. In the future Tx-capable
b3190839cce3 first FPGA version, MCSI Rx only
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4 * FPGA, this logic will also be used to reset the Tx buffer when the clock
b3190839cce3 first FPGA version, MCSI Rx only
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5 * stops.
b3190839cce3 first FPGA version, MCSI Rx only
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6 */
b3190839cce3 first FPGA version, MCSI Rx only
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8 module clk_check (IntClk, MCSI_CLK_sync, MCSI_CLK_running);
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10 input IntClk;
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11 input MCSI_CLK_sync;
b3190839cce3 first FPGA version, MCSI Rx only
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12 output MCSI_CLK_running;
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14 reg [15:0] shift_reg;
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b3190839cce3 first FPGA version, MCSI Rx only
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16 always @(posedge IntClk)
b3190839cce3 first FPGA version, MCSI Rx only
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17 shift_reg <= {shift_reg[14:0],MCSI_CLK_sync};
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19 assign MCSI_CLK_running = (shift_reg != 16'h0000) && (shift_reg != 16'hFFFF);
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21 endmodule