Subversion Repositories s6soc

`timescale 10ns / 100ps

module toplevel(i_clk_8mhz,

                o_qspi_cs_n, o_qspi_sck, io_qspi_dat,

                i_btn, o_led, o_pwm, o_pwm_shutdown_n, o_pwm_gain,

                        i_uart, o_uart,

                i_kp_row, o_kp_col,

                i_gpio, o_gpio,

                io_scl, io_sda);

        input           i_clk_8mhz;

        //

        // Quad SPI Flash

        output  wire            o_qspi_cs_n;

        output  wire            o_qspi_sck;

        inout   wire    [3:0]    io_qspi_dat;

        //

        // General purpose I/O

        input           [1:0]    i_btn;

        output  wire    [3:0]    o_led;

        output  wire            o_pwm, o_pwm_shutdown_n, o_pwm_gain;

        //

        // and our serial port

        input           i_uart;

        output  wire    o_uart;

        // Our keypad

        input           [3:0]    i_kp_row;

        output  wire    [3:0]    o_kp_col;

        // and our GPIO

        input           [15:2]  i_gpio;

        output  wire    [15:2]  o_gpio;

        // and our I2C port

        inout                   io_scl, io_sda;

/////

        wire    ck_zero_0, clk_s; // intermediate_clk, intermediate_clk_n;

        // Clock frequency = (25 / 2) * 8Mhz

        // Clock period = 10 ns

        DCM_SP #(

                .CLKDV_DIVIDE(2.0),

                .CLKFX_DIVIDE(2),

                .CLKFX_MULTIPLY(20),

                .CLKIN_DIVIDE_BY_2("FALSE"),

                .CLKIN_PERIOD(125.0),

                .CLKOUT_PHASE_SHIFT("NONE"),

                .CLK_FEEDBACK("1X"),

                .DESKEW_ADJUST("SYSTEM_SYNCHRONOUS"),

                .DLL_FREQUENCY_MODE("LOW"),

                .DUTY_CYCLE_CORRECTION("TRUE"),

                .PHASE_SHIFT(0),

                .STARTUP_WAIT("TRUE")

        ) u0(   .CLKIN(i_clk_8mhz),

                .CLK0(ck_zero_0),

                .CLKFB(ck_zero_0),

                .CLKFX(clk_s),

                // .CLKFX180(intermediate_clk_n),

                .PSEN(1'b0),

                .RST(1'b0));

        // Generate active-high reset.

        /*

        reg     r_reset;

        initial r_reset = 1'b1;

        always @(posedge i_clk_12mhz)

                r_reset <= 1'b0;

        */

        assign  reset_s = 1'b0;

        wire            rx_stb, tx_stb;

        wire    [7:0]    rx_data, tx_data;

        wire            tx_busy;

        wire    [29:0]   uart_setup;

        wire    rx_break, rx_parity_err, rx_frame_err, rx_ck_uart, tx_break;

        assign  tx_break = 1'b0;

        rxuart  rcvuart(clk_s, reset_s, uart_setup, i_uart, rx_stb, rx_data,

                        rx_break, rx_parity_err, rx_frame_err, rx_ck_uart);

        txuart  tcvuart(clk_s, reset_s, uart_setup, tx_break, tx_stb, tx_data,

                        o_uart, tx_busy);

        wire    [3:0]    qspi_dat;

        wire    [1:0]    qspi_bmod;

        wire    [15:0]   w_gpio;

        busmaster       masterbus(clk_s, reset_s,

                // External ... bus control (if enabled)

                rx_stb, rx_data, tx_stb, tx_data, tx_busy,

                // SPI/SD-card flash

                o_qspi_cs_n, o_qspi_sck, qspi_dat, io_qspi_dat, qspi_bmod,

                // Board lights and switches

                i_btn, o_led, o_pwm, { o_pwm_shutdown_n, o_pwm_gain },

                // Keypad connections

                i_kp_row, o_kp_col,

                // UART control

                uart_setup,

                // GPIO lines

                { i_gpio, io_scl, io_sda }, w_gpio

                );

        assign io_qspi_dat = (~qspi_bmod[1])?({2'b11,1'bz,qspi_dat[0]})

                                :((qspi_bmod[0])?(4'bzzzz):(qspi_dat[3:0]));

        assign  io_sda = (w_gpio[0]) ? 1'bz : 1'b0;

        assign  io_scl = (w_gpio[1]) ? 1'bz : 1'b0;

        assign  o_gpio[15:2] = w_gpio[15:2];

endmodule