Subversion Repositories a-z80

//==============================================================

// Test interrupts unit

//==============================================================

`timescale 100 ns/ 100 ns

module test_interrupts;

// ----------------- CLOCKS AND RESET -----------------

// Define one full T-clock cycle delay

`define T #2

bit clk = 1;

initial repeat (20) #1 clk = ~clk;

logic nreset = 0;

// ----------------- CONTROL ----------------

logic ctl_iff1_iff2_sig=0;

logic ctl_iffx_we_sig=0;

logic ctl_iffx_bit_sig=0;

logic nmi_sig=0;

logic setM1_sig=0;

logic intr_sig=0;

logic ctl_im_we_sig=0;

logic [1:0] db_sig=0;

logic clk_sig=0;

logic ctl_no_ints_sig=0;

// ----------------- STATES ----------------

wire iff1_sig;

wire iff2_sig;

wire im1_sig;

wire im2_sig;

wire in_nmi_sig;

wire in_intr_sig;

// ----------------- TEST -------------------

initial begin

    // Init / reset

    `T  nreset = 1;

        // Test interrupt modes

        db_sig = 2'b10;             // IM1

        ctl_im_we_sig = 1;

    `T  assert(im1_sig==1 && im2_sig==0);

        db_sig = 2'b11;             // IM2

    `T  assert(im1_sig==0 && im2_sig==1);

        db_sig = 2'b00;             // IM0

    `T  assert(im1_sig==0 && im2_sig==0);

        // Test IFF state flags

        assert(iff1_sig==0 && iff2_sig==0);

        ctl_iff1_iff2_sig = 1;

        ctl_iffx_we_sig = 1;

        ctl_iffx_bit_sig = 1;

    `T  assert(iff1_sig==0 && iff2_sig==1);

    `T  assert(iff1_sig==1 && iff2_sig==1);

        ctl_iff1_iff2_sig = 0;

        ctl_iffx_we_sig = 0;

        ctl_iffx_bit_sig = 0;

        // Simulate NMI triggering

        nmi_sig = 1;

    `T  setM1_sig = 1;

    `T  assert(iff1_sig==0 && iff2_sig==1);

    `T  $display("End of test");

end

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

// Instantiate interrupts

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

interrupts interrupts_inst

(

    .ctl_iff1_iff2(ctl_iff1_iff2_sig) , // input  ctl_iff1_iff2_sig

    .nmi(nmi_sig) ,                     // input  nmi_sig

    .setM1(setM1_sig) ,                 // input  setM1_sig

    .intr(intr_sig) ,                   // input  intr_sig

    .ctl_iffx_we(ctl_iffx_we_sig) ,     // input  ctl_iffx_we_sig

    .ctl_iffx_bit(ctl_iffx_bit_sig) ,   // input  ctl_iffx_bit_sig

    .ctl_im_we(ctl_im_we_sig) ,         // input  ctl_im_we_sig

    .db(db_sig) ,                       // input [1:0] db_sig

    .clk(clk) ,                         // input  clk

    .ctl_no_ints(ctl_no_ints_sig) ,     // input  ctl_no_ints_sig

    .nreset(nreset) ,                   // input  nreset

    .iff1(iff1_sig) ,                   // output  iff1_sig

    .iff2(iff2_sig) ,                   // output  iff2_sig

    .im1(im1_sig) ,                     // output  im1_sig

    .im2(im2_sig) ,                     // output  im2_sig

    .in_nmi(in_nmi_sig) ,               // output  in_nmi_sig

    .in_intr(in_intr_sig)               // output  in_intr_sig

);

endmodule