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motilito |
//---------------------------------------------------------------------------------------
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// uart to internal bus top module
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//
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//---------------------------------------------------------------------------------------
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module uart2bus_top
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(
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// global signals
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clock, reset,
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// uart serial signals
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ser_in, ser_out,
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// internal bus to register file
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int_address, int_wr_data, int_write,
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int_rd_data, int_read
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);
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//---------------------------------------------------------------------------------------
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// modules inputs and outputs
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input clock; // global clock input
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input reset; // global reset input
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input ser_in; // serial data input
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output ser_out; // serial data output
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output [15:0] int_address; // address bus to register file
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output [7:0] int_wr_data; // write data to register file
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output int_write; // write control to register file
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output int_read; // read control to register file
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input [7:0] int_rd_data; // data read from register file
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// baud rate configuration, see baud_gen.v for more details.
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// baud rate generator parameters for 115200 baud on 44MHz clock
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`define D_BAUD_FREQ 12'd23
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`define D_BAUD_LIMIT 16'd527
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// baud rate generator parameters for 115200 baud on 40MHz clock
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//`define D_BAUD_FREQ 12'h90
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//`define D_BAUD_LIMIT 16'h0ba5
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// baud rate generator parameters for 9600 baud on 66MHz clock
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//`define D_BAUD_FREQ 12'h10
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//`define D_BAUD_LIMIT 16'h1ACB
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// internal wires
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wire [7:0] tx_data; // data byte to transmit
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wire new_tx_data; // asserted to indicate that there is a new data byte for transmission
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wire tx_busy; // signs that transmitter is busy
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wire [7:0] rx_data; // data byte received
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wire new_rx_data; // signs that a new byte was received
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wire [11:0] baud_freq;
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wire [15:0] baud_limit;
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wire baud_clk;
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//---------------------------------------------------------------------------------------
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// module implementation
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// uart top module instance
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uart_top uart1
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(
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.clock(clock), .reset(reset),
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.ser_in(ser_in), .ser_out(ser_out),
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.rx_data(rx_data), .new_rx_data(new_rx_data),
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.tx_data(tx_data), .new_tx_data(new_tx_data), .tx_busy(tx_busy),
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.baud_freq(baud_freq), .baud_limit(baud_limit),
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.baud_clk(baud_clk)
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);
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// assign baud rate default values
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assign baud_freq = `D_BAUD_FREQ;
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assign baud_limit = `D_BAUD_LIMIT;
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// uart parser instance
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uart_parser #(16) uart_parser1
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(
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.clock(clock), .reset(reset),
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.rx_data(rx_data), .new_rx_data(new_rx_data),
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.tx_data(tx_data), .new_tx_data(new_tx_data), .tx_busy(tx_busy),
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.int_address(int_address), .int_wr_data(int_wr_data), .int_write(int_write),
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.int_rd_data(int_rd_data), .int_read(int_read)
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);
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endmodule
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//---------------------------------------------------------------------------------------
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// Th.. Th.. Th.. Thats all folks !!!
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//---------------------------------------------------------------------------------------
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