Subversion Repositories uart2bus

//---------------------------------------------------------------------------------------

// uart to internal bus top module 

//

//---------------------------------------------------------------------------------------

module uart2bus_top

(

        // global signals 

        clock, reset,

        // uart serial signals 

        ser_in, ser_out,

        // internal bus to register file 

        int_address, int_wr_data, int_write,

        int_rd_data, int_read,

        int_req, int_gnt

);

//---------------------------------------------------------------------------------------

// modules inputs and outputs 

input                   clock;                  // global clock input 

input                   reset;                  // global reset input 

input                   ser_in;                 // serial data input 

output                  ser_out;                // serial data output 

output  [15:0]   int_address;    // address bus to register file 

output  [7:0]    int_wr_data;    // write data to register file 

output                  int_write;              // write control to register file 

output                  int_read;               // read control to register file 

input   [7:0]    int_rd_data;    // data read from register file 

output                  int_req;                // bus access request signal 

input                   int_gnt;                // bus access grant signal 

// baud rate configuration, see baud_gen.v for more details.

// baud rate generator parameters for 115200 baud on 40MHz clock 

`define D_BAUD_FREQ                     12'h90

`define D_BAUD_LIMIT            16'h0ba5

// baud rate generator parameters for 115200 baud on 44MHz clock 

// `define D_BAUD_FREQ                  12'd23

// `define D_BAUD_LIMIT         16'd527

// baud rate generator parameters for 9600 baud on 66MHz clock 

//`define D_BAUD_FREQ           12'h10

//`define D_BAUD_LIMIT          16'h1ACB

// internal wires 

wire    [7:0]    tx_data;                // data byte to transmit 

wire                    new_tx_data;    // asserted to indicate that there is a new data byte for transmission 

wire                    tx_busy;                // signs that transmitter is busy 

wire    [7:0]    rx_data;                // data byte received 

wire                    new_rx_data;    // signs that a new byte was received 

wire    [11:0]   baud_freq;

wire    [15:0]   baud_limit;

wire                    baud_clk;

//---------------------------------------------------------------------------------------

// module implementation 

// uart top module instance 

uart_top uart1

(

        .clock(clock), .reset(reset),

        .ser_in(ser_in), .ser_out(ser_out),

        .rx_data(rx_data), .new_rx_data(new_rx_data),

        .tx_data(tx_data), .new_tx_data(new_tx_data), .tx_busy(tx_busy),

        .baud_freq(baud_freq), .baud_limit(baud_limit),

        .baud_clk(baud_clk)

);

// assign baud rate default values 

assign baud_freq = `D_BAUD_FREQ;

assign baud_limit = `D_BAUD_LIMIT;

// uart parser instance 

uart_parser #(16) uart_parser1

(

        .clock(clock), .reset(reset),

        .rx_data(rx_data), .new_rx_data(new_rx_data),

        .tx_data(tx_data), .new_tx_data(new_tx_data), .tx_busy(tx_busy),

        .int_address(int_address), .int_wr_data(int_wr_data), .int_write(int_write),

        .int_rd_data(int_rd_data), .int_read(int_read),

        .int_req(int_req), .int_gnt(int_gnt)

);

endmodule

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//                                              Th.. Th.. Th.. Thats all folks !!!

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