module cmsdk_mcu_system #(
  parameter BASEADDR_GPIO0  = 32'h4001_0000, // GPIO0 peripheral base address
  parameter BASEADDR_GPIO1  = 32'h4001_1000, // GPIO1 peripheral base address
  parameter BE              = 0,   // 1: Big endian 0: little endian
  parameter BKPT            = 4,   // Number of breakpoint comparators
  parameter DBG             = 1,   // Debug configuration
  parameter NUMIRQ          = 32,  // NUM of IRQ
  parameter SMUL            = 0,   // Multiplier configuration
  parameter SYST            = 1,   // SysTick
  parameter WIC             = 0,   // Wake-up interrupt controller support
  parameter WICLINES        = 34,  // Supported WIC lines
  parameter WPT             = 2,   // Number of DWT comparators

  // Location of the System ROM Table.
  parameter BASEADDR_SYSROMTABLE = 32'hF000_0000

 )
 (
  input  wire               FCLK,             // Free running clock
  input  wire               HCLK,             // AHB clock(from PMU)
  input  wire               DCLK,             // Debug system clock (from PMU)
  input  wire               SCLK,             // System clock
  input  wire               HRESETn,          // AHB and System reset
  input  wire               PORESETn,         // Power on reset
  input  wire               DBGRESETn,        // Debug reset
  input  wire               PCLK,             // Peripheral clock
  input  wire               PCLKG,            // Gated Peripheral bus clock
  input  wire               PRESETn,          // Peripheral system and APB reset
  input  wire               PCLKEN,           // Clock divide control for AHB to APB bridge

`ifdef ARM_DESIGNSTART_FPGA
  input  wire               zbt_boot_ctrl,    // FPGA Only: Set to 1 to boot from ZBT SRAM
`endif
  output wire  [31:0]       HADDR,            // AHB to memory blocks - address
  output wire   [1:0]       HTRANS,           // AHB to memory blocks - transfer ctrl
  output wire   [2:0]       HSIZE,            // AHB to memory blocks - transfer size
  output wire               HWRITE,           // AHB to memory blocks - write ctrl
  output wire  [31:0]       HWDATA,           // AHB to memory blocks - write data
  output wire               HREADY,           // AHB to memory blocks - AHB ready

  output wire               flash_hsel,       // AHB to flash memory - select
  input  wire               flash_hreadyout,  // AHB from flash blocks - ready
  input  wire  [31:0]       flash_hrdata,     // AHB from flash blocks - read data
  input  wire               flash_hresp,      // AHB from flash blocks - response

  output wire               sram_hsel,        // AHB to SRAM - select
  input  wire               sram_hreadyout,   // AHB from SRAM - ready
  input  wire  [31:0]       sram_hrdata,      // AHB from SRAM - read data
  input  wire               sram_hresp,       // AHB from SRAM - response

                                              // Optional : only if BOOT_MEM_TYPE!=0
  output wire               boot_hsel,        // AHB to boot loader - select
  input  wire               boot_hreadyout,   // AHB from boot loader - ready
  input  wire  [31:0]       boot_hrdata,      // AHB from boot loader - read data
  input  wire               boot_hresp,       // AHB from boot loader - response

  output wire               APBACTIVE,        // APB bus active (for clock gating of PCLKG)
  output wire               SLEEPING,         // Processor status - sleeping
  output wire               SLEEPDEEP,        // Processor status - deep sleep
  output wire               SYSRESETREQ,      // Processor control - system reset request
  output wire               WDOGRESETREQ,     // Watchdog reset request
  output wire               LOCKUP,           // Processor status - Locked up
  output wire               LOCKUPRESET,      // System Controller cfg - reset if lockup
  output wire               PMUENABLE,        // System Controller cfg - Enable PMU

  input  wire               nTRST,            // JTAG - Test reset (active low)
  input  wire               SWDITMS,          // JTAG/SWD - TMS / SWD data input
  input  wire               SWCLKTCK,         // JTAG/SWD - TCK / SWCLK
  input  wire               TDI,              // JTAG - Test data in
  output wire               TDO,              // JTAG - Test data out
  output wire               nTDOEN,           // JTAG - Test data out enable (active low)
  output wire               SWDO,             // SWD - SWD data output
  output wire               SWDOEN,           // SWD - SWD data output enable
  
  input  wire               uart0_rxd,        // Uart 0 receive data
  output wire               uart0_txd,        // Uart 0 transmit data
  output wire               uart0_txen,       // Uart 0 transmit data enable
  input  wire               uart1_rxd,        // Uart 1 receive data
  output wire               uart1_txd,        // Uart 1 transmit data
  output wire               uart1_txen,       // Uart 1 transmit data enable
  input  wire               uart2_rxd,        // Uart 2 receive data
  output wire               uart2_txd,        // Uart 2 transmit data
  output wire               uart2_txen,       // Uart 2 transmit data enable

  input  wire               timer0_extin,     // Timer 0 external input
  input  wire               timer1_extin,     // Timer 1 external input

  input  wire  [15:0]       p0_in,            // GPIO 0 inputs
  output wire  [15:0]       p0_out,           // GPIO 0 outputs
  output wire  [15:0]       p0_outen,         // GPIO 0 output enables
  output wire  [15:0]       p0_altfunc,       // GPIO 0 alternate function (pin mux)
  input  wire  [15:0]       p1_in,            // GPIO 1 inputs
  output wire  [15:0]       p1_out,           // GPIO 1 outputs
  output wire  [15:0]       p1_outen,         // GPIO 1 output enables
  output wire  [15:0]       p1_altfunc,       // GPIO 1 alternate function (pin mux)

`ifdef ARM_DESIGNSTART_FPGA
  input  wire               spi_interrupt,    // FPGA Only: V2M-MPS2 SPI interrupt
  input  wire               i2s_interrupt,    // FPGA Only: V2M-MPS2 I2S interrupt
  input  wire               eth_interrupt,    // FPGA Only: V2M-MPS2 Ethernet interrupt
  input  wire               ts_interrupt,     // FPGA Only: V2M-MPS2 Touch screen interrupt
  input  wire               gpio2_interrupt,  // FPGA Only: V2M-MPS2 GPIO 2
  input  wire               gpio3_interrupt,  // FPGA Only: V2M-MPS2 GPIO 3
`endif
  input  wire               DFTSE);           // dummy scan enable port for synthesis

  // -------------------------------
  // Internal signals
  // -------------------------------
  wire              HCLKSYS;        // System AHB clock

  // System bus from processor
  wire     [31:0]   cm0_haddr;
  wire     [1:0]    cm0_htrans;
  wire     [2:0]    cm0_hsize;
  wire     [2:0]    cm0_hburst;
  wire     [3:0]    cm0_hprot;
  wire              cm0_hmaster;
  wire              cm0_hmastlock;
  wire              cm0_hwrite;
  wire     [31:0]   cm0_hwdata;
  wire     [31:0]   cm0_hrdata;
  wire              cm0_hready;
  wire              cm0_hresp;

  // Bit band wrapper bus between CPU and the reset of the system
  wire     [31:0]   cm_haddr;
  wire     [1:0]    cm_htrans;
  wire     [2:0]    cm_hsize;
  wire     [2:0]    cm_hburst;
  wire     [3:0]    cm_hprot;
  wire              cm_hmastlock;
  wire              cm_hmaster;
  wire              cm_hwrite;
  wire     [31:0]   cm_hwdata;
  wire     [31:0]   cm_hrdata;
  wire              cm_hready;
  wire              cm_hreadyout;
  wire              cm_hresp;

  // System bus
  wire              sys_hselm;  // Note: the sys_hselm signal is for protocol checking only.
  wire     [31:0]   sys_haddr;
  wire     [1:0]    sys_htrans;
  wire     [2:0]    sys_hsize;
  wire     [2:0]    sys_hburst;
  wire     [3:0]    sys_hprot;
  wire              sys_hmaster;
  wire              sys_hmastlock;
  wire              sys_hwrite;
  wire     [31:0]   sys_hwdata;
  wire     [31:0]   sys_hrdata;
  wire              sys_hready;
  wire              sys_hreadyout;
  wire              sys_hresp;

  wire              defslv_hsel;   // AHB default slave signals
  wire              defslv_hreadyout;
  wire     [31:0]   defslv_hrdata;
  wire              defslv_hresp;

  wire              apbsys_hsel;  // APB subsystem AHB interface signals
  wire              apbsys_hreadyout;
  wire     [31:0]   apbsys_hrdata;
  wire              apbsys_hresp;

  wire              gpio0_hsel;   // AHB GPIO bus interface signals
  wire              gpio0_hreadyout;
  wire     [31:0]   gpio0_hrdata;
  wire              gpio0_hresp;

  wire              gpio1_hsel;   // AHB GPIO bus interface signals
  wire              gpio1_hreadyout;
  wire     [31:0]   gpio1_hrdata;
  wire              gpio1_hresp;

  wire              sysctrl_hsel;  // System control bus interface signals
  wire              sysctrl_hreadyout;
  wire     [31:0]   sysctrl_hrdata;
  wire              sysctrl_hresp;

  // MTB (Only available to the Cortex-M0+)
  wire              HSELMTB;
  wire              HREADYOUTMTB;
  wire     [31:0]   HRDATAMTB;
  wire              HRESPMTB;
  wire              HSELSFR;
  wire              HSELRAM;

  // System ROM Table
  wire              sysrom_hsel;      // AHB to System ROM Table - select
  wire              sysrom_hreadyout; // AHB from System ROM Table - ready
  wire     [31:0]   sysrom_hrdata;    // AHB from System ROM Table - read data
  wire              sysrom_hresp;     // AHB from System ROM Table - response

  wire [1:0]        sys_hmaster_i;

  // APB expansion port signals
  wire     [11:0]   exp_paddr;
  wire     [31:0]   exp_pwdata;
  wire              exp_pwrite;
  wire              exp_penable;

  wire     [33:0]   WICSENSE;
  wire CDBGPWRUPREQ;
  wire              remap_ctrl;

  // Interrupt request
  wire     [31:0]   intisr_cm0;
  wire              intnmi_cm0;
  wire     [15:0]   gpio0_intr;
  wire              gpio0_combintr;
  wire              gpio1_combintr;
  wire     [31:0]   apbsubsys_interrupt;
  wire              watchdog_interrupt;

     // I/O Port
  wire              IOMATCH;
  wire     [31:0]   IORDATA;
  wire              IOTRANS;
  wire              IOWRITE;
  wire     [31:0]   IOCHECK;
  wire     [31:0]   IOADDR;
  wire     [ 1:0]   IOSIZE;
  wire              IOMASTER;
  wire              IOPRIV;
  wire     [31:0]   IOWDATA;

  // event signals
  wire              TXEV;
  wire              RXEV;

  // SysTick timer signals
  wire              STCLKEN;
  wire     [25:0]   STCALIB;

  // Processor debug signals
  wire              DBGRESTART;
  wire              DBGRESTARTED;
  wire              EDBGRQ;

  // Processor status
  wire              HALTED;
  wire              SPECHTRANS;
  wire              CODENSEQ;
  wire              SHAREABLE;

// Only used in FPGA configuration, tie-off in RTL version
`ifndef ARM_DESIGNSTART_FPGA
  wire       spi_interrupt   = 1'b0;
  wire       i2s_interrupt   = 1'b0;
  wire       eth_interrupt   = 1'b0;
  wire       ts_interrupt    = 1'b0;
  wire       gpio2_interrupt = 1'b0;
  wire       gpio3_interrupt = 1'b0;
`endif
    
  assign   HCLKSYS  = HCLK;


//instantiate the DesignStart Cortex M0 Integration Layer
CORTEXM0INTEGRATION
u_cortexm0integration
(
  // CLOCK AND RESETS
  .FCLK          (FCLK),
  .SCLK          (SCLK),
  .HCLK          (HCLK),
  .DCLK          (DCLK),
  .PORESETn      (PORESETn),
  .DBGRESETn     (DBGRESETn),
  .HRESETn       (HRESETn),
  .SWCLKTCK      (SWCLKTCK),
  .nTRST         (nTRST),

  // AHB-LITE MASTER PORT
  .HADDR         (cm0_haddr),
  .HBURST        (cm0_hburst),
  .HMASTLOCK     (cm0_hmastlock),
  .HPROT         (cm0_hprot),
  .HSIZE         (cm0_hsize),
  .HTRANS        (cm0_htrans),
  .HWDATA        (cm0_hwdata),
  .HWRITE        (cm0_hwrite),
  .HRDATA        (cm0_hrdata),
  .HREADY        (cm0_hready),
  .HRESP         (cm0_hresp),
  .HMASTER       (),

  // CODE SEQUENTIALITY AND SPECULATION
  .CODENSEQ      (CODENSEQ),
  .CODEHINTDE    (),
  .SPECHTRANS    (),

  // DEBUG
  .SWDITMS       (SWDITMS),
  .TDI           (1'b0),
  .SWDO          (SWDO),
  .SWDOEN        (SWDOEN),
  .TDO           (TDO),
  .nTDOEN        (nTDOEN),
  .DBGRESTART    (1'b0),
  .DBGRESTARTED  (DBGRESTARTED),
  .EDBGRQ        (1'b0),
  .HALTED        (HALTED),

  // MISC
  .NMI            (1'b0),        // Non-maskable interrupt input
  .IRQ            (32'h00000000),        // Interrupt request inputs
  .TXEV           (TXEV),              // Event output (SEV executed)
  .RXEV           (1'b0),              // Event input
  .LOCKUP         (LOCKUP),            // Core is locked-up
  .SYSRESETREQ    (SYSRESETREQ),       // System reset request
  .STCALIB        (STCALIB),           // SysTick calibration register value
  .STCLKEN        (STCLKEN),           // SysTick SCLK clock enable
  .IRQLATENCY     (8'h00),
  .ECOREVNUM      (28'haa),

  // POWER MANAGEMENT
  .GATEHCLK      (),
  .SLEEPING      (SLEEPING),           // Core and NVIC sleeping
  .SLEEPDEEP     (SLEEPDEEP),
  .WAKEUP        (),
  .WICSENSE      (WICSENSE),
  .SLEEPHOLDREQn (1'b1),
  .SLEEPHOLDACKn (),
  .WICENREQ      (1'b0),
  .WICENACK      (),
  .CDBGPWRUPREQ  (CDBGPWRUPREQ),
  .CDBGPWRUPACK  (CDBGPWRUPREQ),

  // SCAN IO
  .SE            (1'b1),
  .RSTBYPASS     (1'b0)
);

// Force connect some signals to 0 or 1
   assign        cm0_hmaster  = 1'b0;


  // Unused debug feature
  assign   DBGRESTART = 1'b0; // multi-core synchronous restart from halt
  assign   EDBGRQ     = 1'b0; // multi-core synchronous halt request

  assign   RXEV = 1'b0;

  // No MTB in Cortex-M0
  assign   HRDATAMTB    = {32{1'b0}};
  assign   HREADYOUTMTB = 1'b0;
  assign   HRESPMTB     = 1'b0;

  // -------------------------------
  // AHB system
  // -------------------------------

  // No bitband wrapper, direct signal connections
  assign   cm_haddr[31:0]  = cm0_haddr[31:0];
  assign   cm_htrans[1:0]  = cm0_htrans[1:0];
  assign   cm_hsize[2:0]   = cm0_hsize[2:0];
  assign   cm_hburst[2:0]  = cm0_hburst[2:0];
  assign   cm_hprot[3:0]   = cm0_hprot[3:0];
  assign   cm_hmaster      = cm0_hmaster;
  assign   cm_hmastlock    = cm0_hmastlock;
  assign   cm_hwrite       = cm0_hwrite;
  assign   cm_hwdata[31:0] = cm0_hwdata[31:0];
  assign   cm_hready       = cm0_hready;
  assign   cm0_hrdata[31:0]= cm_hrdata[31:0];
  assign   cm0_hready      = cm_hreadyout;
  assign   cm0_hresp       = cm_hresp;

  // No DMA controller - no need to have master multiplexer
  // direct connection from cpu to system bus if DMA is not presented
  assign   sys_haddr[31:0] = cm_haddr[31:0];
  assign   sys_htrans[1:0] = cm_htrans[1:0];
  assign   sys_hsize[2:0]  = cm_hsize[2:0];
  assign   sys_hburst[2:0] = cm_hburst[2:0];
  assign   sys_hprot[3:0]  = cm_hprot[3:0];
  assign   sys_hmaster     = cm_hmaster;
  assign   sys_hmastlock   = cm_hmastlock;
  assign   sys_hwrite      = cm_hwrite;
  assign   sys_hwdata[31:0]= cm_hwdata[31:0];
  assign   sys_hready      = cm_hready;
  assign   cm_hrdata[31:0] = sys_hrdata[31:0];
  assign   cm_hreadyout    = sys_hreadyout;
  assign   cm_hresp        = sys_hresp;
  assign   sys_hmaster_i   = 2'b00;

  // AHB address decode
  cmsdk_mcu_addr_decode #(
     .BASEADDR_GPIO0       (BASEADDR_GPIO0),
     .BASEADDR_GPIO1       (BASEADDR_GPIO1),
     .BOOT_LOADER_PRESENT  (1'b0),
     .BASEADDR_SYSROMTABLE (BASEADDR_SYSROMTABLE)
    )
    u_addr_decode (
    // System Address
    .haddr         (sys_haddr),
    .remap_ctrl    (remap_ctrl),
`ifdef ARM_DESIGNSTART_FPGA
    .zbt_boot_ctrl (zbt_boot_ctrl),
`endif
    .boot_hsel     (boot_hsel),
    .flash_hsel    (flash_hsel),
    .sram_hsel     (sram_hsel),
    .apbsys_hsel   (apbsys_hsel),
    .gpio0_hsel    (gpio0_hsel),
    .gpio1_hsel    (gpio1_hsel),
    .sysctrl_hsel  (sysctrl_hsel),
    .sysrom_hsel   (sysrom_hsel),
    .defslv_hsel   (defslv_hsel),
    .hselmtb       (HSELMTB),
    .hselram       (HSELRAM),
    .hselsfr       (HSELSFR)
  );


  // AHB slave multiplexer
  cmsdk_ahb_slave_mux #(
    .PORT0_ENABLE  (1),
    .PORT1_ENABLE  (1),
    .PORT2_ENABLE  (0),
    .PORT3_ENABLE  (1),
    .PORT4_ENABLE  (1),
    .PORT5_ENABLE  (1),
    .PORT6_ENABLE  (1),
    .PORT7_ENABLE  (1),
    .PORT8_ENABLE  (1),
    .PORT9_ENABLE  (0),
    .DW            (32)
    )
    u_ahb_slave_mux_sys_bus (
    .HCLK         (HCLKSYS),
    .HRESETn      (HRESETn),
    .HREADY       (sys_hready),
    .HSEL0        (flash_hsel),      // Input Port 0
    .HREADYOUT0   (flash_hreadyout),
    .HRESP0       (flash_hresp),
    .HRDATA0      (flash_hrdata),
    .HSEL1        (sram_hsel),       // Input Port 1
    .HREADYOUT1   (sram_hreadyout),
    .HRESP1       (sram_hresp),
    .HRDATA1      (sram_hrdata),
    .HSEL2        (boot_hsel),       // Input Port 2
    .HREADYOUT2   (boot_hreadyout),
    .HRESP2       (boot_hresp),
    .HRDATA2      (boot_hrdata),
    .HSEL3        (defslv_hsel),     // Input Port 3
    .HREADYOUT3   (defslv_hreadyout),
    .HRESP3       (defslv_hresp),
    .HRDATA3      (defslv_hrdata),
    .HSEL4        (apbsys_hsel),     // Input Port 4
    .HREADYOUT4   (apbsys_hreadyout),
    .HRESP4       (apbsys_hresp),
    .HRDATA4      (apbsys_hrdata),
    .HSEL5        (gpio0_hsel),      // Input Port 5
    .HREADYOUT5   (gpio0_hreadyout),
    .HRESP5       (gpio0_hresp),
    .HRDATA5      (gpio0_hrdata),
    .HSEL6        (gpio1_hsel),      // Input Port 6
    .HREADYOUT6   (gpio1_hreadyout),
    .HRESP6       (gpio1_hresp),
    .HRDATA6      (gpio1_hrdata),
    .HSEL7        (sysctrl_hsel),    // Input Port 7
    .HREADYOUT7   (sysctrl_hreadyout),
    .HRESP7       (sysctrl_hresp),
    .HRDATA7      (sysctrl_hrdata),
    .HSEL8        (sysrom_hsel),     // Input Port 8
    .HREADYOUT8   (sysrom_hreadyout),
    .HRESP8       (sysrom_hresp),
    .HRDATA8      (sysrom_hrdata),
    .HSEL9        (HSELMTB),         // Input Port 9
    .HREADYOUT9   (HREADYOUTMTB),
    .HRESP9       (HRESPMTB),
    .HRDATA9      (HRDATAMTB),

    .HREADYOUT    (sys_hreadyout),   // Outputs
    .HRESP        (sys_hresp),
    .HRDATA       (sys_hrdata)
  );

  // Default slave
  cmsdk_ahb_default_slave u_ahb_default_slave_1 (
    .HCLK         (HCLKSYS),
    .HRESETn      (HRESETn),
    .HSEL         (defslv_hsel),
    .HTRANS       (sys_htrans),
    .HREADY       (sys_hready),
    .HREADYOUT    (defslv_hreadyout),
    .HRESP        (defslv_hresp)
  );

  assign   defslv_hrdata = 32'h00000000; // Default slave do not have read data


  // -------------------------------
  // System ROM Table
  // -------------------------------
  cmsdk_ahb_cs_rom_table
   #(//.JEPID                             (),
     //.JEPCONTINUATION                   (),
     //.PARTNUMBER                        (),
     //.REVISION                          (),
     .BASE              (BASEADDR_SYSROMTABLE),
     // Entry 0 = Cortex-M0+ Processor
     .ENTRY0BASEADDR    (32'hE00FF000),
     .ENTRY0PRESENT     (1'b1),
     // Entry 1 = CoreSight MTB-M0+
     .ENTRY1BASEADDR    (32'hF0200000),
     .ENTRY1PRESENT     (0))
    u_system_rom_table
    (//Outputs
     .HRDATA                            (sysrom_hrdata[31:0]),
     .HREADYOUT                         (sysrom_hreadyout),
     .HRESP                             (sysrom_hresp),
     //Inputs
     .HCLK                              (HCLKSYS),
     .HSEL                              (sysrom_hsel),
     .HADDR                             (sys_haddr[31:0]),
     .HBURST                            (sys_hburst[2:0]),
     .HMASTLOCK                         (sys_hmastlock),
     .HPROT                             (sys_hprot[3:0]),
     .HSIZE                             (sys_hsize[2:0]),
     .HTRANS                            (sys_htrans[1:0]),
     .HWDATA                            (sys_hwdata[31:0]),
     .HWRITE                            (sys_hwrite),
     .HREADY                            (sys_hready),
     .ECOREVNUM                         (4'h0));

  // -------------------------------
  // Peripherals
  // -------------------------------

  cmsdk_mcu_sysctrl #(.BE (BE))
    u_cmsdk_mcu_sysctrl
  (
   // AHB Inputs
    .HCLK         (HCLKSYS),
    .HRESETn      (HRESETn),
    .FCLK         (FCLK),
    .PORESETn     (PORESETn),
    .HSEL         (sysctrl_hsel),
    .HREADY       (sys_hready),
    .HTRANS       (sys_htrans),
    .HSIZE        (sys_hsize),
    .HWRITE       (sys_hwrite),
    .HADDR        (sys_haddr[11:0]),
    .HWDATA       (sys_hwdata),
   // AHB Outputs
    .HREADYOUT    (sysctrl_hreadyout),
    .HRESP        (sysctrl_hresp),
    .HRDATA       (sysctrl_hrdata),
   // Reset information
    .SYSRESETREQ  (SYSRESETREQ),
    .WDOGRESETREQ (WDOGRESETREQ),
    .LOCKUP       (LOCKUP),
    // Engineering-change-order revision bits
    .ECOREVNUM    (4'h0),
   // System control signals
    .REMAP        (remap_ctrl),
    .PMUENABLE    (PMUENABLE),
    .LOCKUPRESET  (LOCKUPRESET)
   );


  // GPIO is driven from the AHB
  cmsdk_ahb_gpio #(
    .ALTERNATE_FUNC_MASK     (16'h0000), // No pin muxing for Port #0
    .ALTERNATE_FUNC_DEFAULT  (16'h0000), // All pins default to GPIO
    .BE                      (BE)
    )
    u_ahb_gpio_0  (
   // AHB Inputs
    .HCLK         (HCLKSYS),
    .HRESETn      (HRESETn),
    .FCLK         (FCLK),
    .HSEL         (gpio0_hsel),
    .HREADY       (sys_hready),
    .HTRANS       (sys_htrans),
    .HSIZE        (sys_hsize),
    .HWRITE       (sys_hwrite),
    .HADDR        (sys_haddr[11:0]),
    .HWDATA       (sys_hwdata),
   // AHB Outputs
    .HREADYOUT    (gpio0_hreadyout),
    .HRESP        (gpio0_hresp),
    .HRDATA       (gpio0_hrdata),

    .ECOREVNUM    (4'h0),// Engineering-change-order revision bits

    .PORTIN       (p0_in),   // GPIO Interface inputs
    .PORTOUT      (p0_out),  // GPIO Interface outputs
    .PORTEN       (p0_outen),
    .PORTFUNC     (p0_altfunc), // Alternate function control

    .GPIOINT      (gpio0_intr[15:0]),  // Interrupt outputs
    .COMBINT      (gpio0_combintr)
  );


  cmsdk_ahb_gpio #(
    .ALTERNATE_FUNC_MASK     (16'h002A), // pin muxing for Port #1
    .ALTERNATE_FUNC_DEFAULT  (16'h0000), // All pins default to GPIO
    .BE                      (BE)
    )
    u_ahb_gpio_1  (
   // AHB Inputs
    .HCLK         (HCLKSYS),
    .HRESETn      (HRESETn),
    .FCLK         (FCLK),
    .HSEL         (gpio1_hsel),
    .HREADY       (sys_hready),
    .HTRANS       (sys_htrans),
    .HSIZE        (sys_hsize),
    .HWRITE       (sys_hwrite),
    .HADDR        (sys_haddr[11:0]),
    .HWDATA       (sys_hwdata),
   // AHB Outputs
    .HREADYOUT    (gpio1_hreadyout),
    .HRESP        (gpio1_hresp),
    .HRDATA       (gpio1_hrdata),

    .ECOREVNUM    (4'h0),// Engineering-change-order revision bits

    .PORTIN       (p1_in),   // GPIO Interface inputs
    .PORTOUT      (p1_out),  // GPIO Interface outputs
    .PORTEN       (p1_outen),
    .PORTFUNC     (p1_altfunc), // Alternate function control

    .GPIOINT      (),  // Interrupt outputs
    .COMBINT      (gpio1_combintr)
  );

  assign IOMATCH = 1'b0;
  assign IORDATA = {32{(1'b0)}};

  // APB subsystem for timers, UARTs
  cmsdk_apb_subsystem #(
    .APB_EXT_PORT12_ENABLE   (0),
    .APB_EXT_PORT13_ENABLE   (0),
    .APB_EXT_PORT14_ENABLE   (0),
    .APB_EXT_PORT15_ENABLE   (0),
    .INCLUDE_IRQ_SYNCHRONIZER(0),
    .INCLUDE_APB_TEST_SLAVE  (0),
    .INCLUDE_APB_TIMER0      (0),  // Include simple timer #0
    .INCLUDE_APB_TIMER1      (0),  // Include simple timer #1
    .INCLUDE_APB_DUALTIMER0  (0),  // Include dual timer module
    .INCLUDE_APB_UART0       (1),  // Include simple UART #0
    .INCLUDE_APB_UART1       (0),  // Include simple UART #1
    .INCLUDE_APB_UART2       (0),  // Include simple UART #2.
    .INCLUDE_APB_WATCHDOG    (0),  // Include APB watchdog module
    .BE                      (BE)
     )
  u_apb_subsystem(

  // AHB interface for AHB to APB bridge
    .HCLK          (HCLKSYS),
    .HRESETn       (HRESETn),

    .HSEL          (apbsys_hsel),
    .HADDR         (sys_haddr[15:0]),
    .HTRANS        (sys_htrans[1:0]),
    .HWRITE        (sys_hwrite),
    .HSIZE         (sys_hsize),
    .HPROT         (sys_hprot),
    .HREADY        (sys_hready),
    .HWDATA        (sys_hwdata[31:0]),

    .HREADYOUT     (apbsys_hreadyout),
    .HRDATA        (apbsys_hrdata),
    .HRESP         (apbsys_hresp),

  // APB clock and reset
    .PCLK          (PCLK),
    .PCLKG         (PCLKG),
    .PCLKEN        (PCLKEN),
    .PRESETn       (PRESETn),

  // APB extension ports
    .PADDR         (exp_paddr[11:0]),
    .PWRITE        (exp_pwrite),
    .PWDATA        (exp_pwdata[31:0]),
    .PENABLE       (exp_penable),

    .ext12_psel    (),
    .ext13_psel    (),
    .ext14_psel    (),
    .ext15_psel    (),

  // Input from APB devices on APB expansion ports
    .ext12_prdata  (32'h00000000),
    .ext12_pready  (1'b1),
    .ext12_pslverr (1'b0),

    .ext13_prdata  (32'h00000000),
    .ext13_pready  (1'b1),
    .ext13_pslverr (1'b0),

    .ext14_prdata  (32'h00000000),
    .ext14_pready  (1'b1),
    .ext14_pslverr (1'b0),

    .ext15_prdata  (32'h00000000),
    .ext15_pready  (1'b1),
    .ext15_pslverr (1'b0),

    .APBACTIVE     (APBACTIVE),  // Status Output for clock gating

  // Peripherals
    // UART
    .uart0_rxd     (uart0_rxd),
    .uart0_txd     (uart0_txd),
    .uart0_txen    (uart0_txen),

    .uart1_rxd     (uart1_rxd),
    .uart1_txd     (uart1_txd),
    .uart1_txen    (uart1_txen),

    .uart2_rxd     (uart2_rxd),
    .uart2_txd     (uart2_txd),
    .uart2_txen    (uart2_txen),

    // Timer
    .timer0_extin  (timer0_extin),
    .timer1_extin  (timer1_extin),

  // Interrupt outputs
    .apbsubsys_interrupt (apbsubsys_interrupt),
    .watchdog_interrupt  (watchdog_interrupt),
   // reset output
    .watchdog_reset      (WDOGRESETREQ)
  );

  // Connect system bus to external
  assign   HADDR  = sys_haddr;
  assign   HTRANS = sys_htrans;
  assign   HSIZE  = sys_hsize;
  assign   HWRITE = sys_hwrite;
  assign   HWDATA = sys_hwdata;
  assign   HREADY = sys_hready;

  // -------------------------------
  // Interrupt assignment
  // -------------------------------
  // Changed from CMSDK:
  // IRQ[12] is used as combined UART overflow interrupt
  
  assign intnmi_cm0        = watchdog_interrupt;
  assign intisr_cm0[ 5: 0] = apbsubsys_interrupt[ 5: 0];
  assign intisr_cm0[ 6]    = apbsubsys_interrupt[ 6]   | gpio0_combintr | gpio2_interrupt;
  assign intisr_cm0[ 7]    = apbsubsys_interrupt[ 7]   | gpio1_combintr | gpio3_interrupt;
  assign intisr_cm0[10: 8] = apbsubsys_interrupt[10: 8];
  assign intisr_cm0[11]    = apbsubsys_interrupt[11]   | spi_interrupt; 
  assign intisr_cm0[12]    = |apbsubsys_interrupt[14: 12]; // UART Overflow interrupts
  assign intisr_cm0[13]    = eth_interrupt;                // V2M-MPS2 Ethernet
  assign intisr_cm0[14]    = i2s_interrupt;                // V2M-MPS2 Ethernet
  assign intisr_cm0[15]    = apbsubsys_interrupt[15]   | ts_interrupt; // Also DMA if integrated
  assign intisr_cm0[31:16] = apbsubsys_interrupt[31:16]| gpio0_intr;

  // -------------------------------
  // SysTick signals
  // -------------------------------
  cmsdk_mcu_stclkctrl
   #(.DIV_RATIO (18'd01000))
   u_cmsdk_mcu_stclkctrl (
    .FCLK      (FCLK),
    .SYSRESETn (HRESETn),

    .STCLKEN   (STCLKEN),
    .STCALIB   (STCALIB)
    );

 // --------------------------------------------------------------------------------
 // Verification components
 // --------------------------------------------------------------------------------
`ifdef ARM_AHB_ASSERT_ON
  // AHB protocol checker for process bus
  AhbLitePC #(
      .ADDR_WIDTH                           (32),
      .DATA_WIDTH                           (32),
      .BIG_ENDIAN                           (BE),
      .MASTER_TO_INTERCONNECT               ( 1),
      .EARLY_BURST_TERMINATION              ( 0),
      // Property type (0=prove, 1=assume, 2=ignore)
      .MASTER_REQUIREMENT_PROPTYPE          ( 0),
      .MASTER_RECOMMENDATION_PROPTYPE       ( 0),
      .MASTER_XCHECK_PROPTYPE               ( 0),
      .SLAVE_REQUIREMENT_PROPTYPE           ( 0),
      .SLAVE_RECOMMENDATION_PROPTYPE        ( 0),
      .SLAVE_XCHECK_PROPTYPE                ( 0),
      .INTERCONNECT_REQUIREMENT_PROPTYPE    ( 0),
      .INTERCONNECT_RECOMMENDATION_PROPTYPE ( 0),
      .INTERCONNECT_XCHECK_PROPTYPE         ( 0)
   ) u_AhbLitePC_processor
  (
   // clock
   .HCLK         (HCLKSYS),

   // active low reset
   .HRESETn      (HRESETn),

   // Main Master signals
   .HADDR        (cm0_haddr),
   .HTRANS       (cm0_htrans),
   .HWRITE       (cm0_hwrite),
   .HSIZE        (cm0_hsize),
   .HBURST       (cm0_hburst),
   .HPROT        (cm0_hprot),
   .HWDATA       (cm0_hwdata),

   // Main Decoder signals
   .HSELx        (1'bx), // Ignored for this instance

   // Main Slave signals
   .HRDATA       (cm0_hrdata),
   .HREADY       (cm0_hready),
   .HREADYOUT    (1'bx),  // Ignored for this instance
   .HRESP        (cm0_hresp),

   // HMASTER, // NOTE: not used

   .HMASTLOCK    (cm0_hmastlock)
   );
`endif

endmodule