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/*
* Topmost module in synthesis. It instantiates the intercon together with
* stack machine as master and 3 slaves:
* slave 0 - embedded RAM (256x16) with memory initialized from file
* slave 1 - SRAM
* slave 2 - VGA text-mode controller
*
* The memory map from stack machine's viewpoint is as follows:
* h000000 - h0001FF - embedded RAM
* h000200 - h07FFFF - undefined (actually, repetitions of embedded RAM)
* h080000 - h0FFFFF - SRAM
* h100000 - h1009FF - VGA text memory
* h100A00 - h100A01 - VGA power-on register
* h100A02 - h100FFF - undefined (actually, repetitions of VGA power-on reg)
* h101000 - h17FFFF - undefined (actually, repetitions of VGA memory)
* h180000 - h1FFFFF - read as 0, write as don't care
*/
`default_nettype none
`ifndef ROM_WORDS_COUNT
`error_ROM_WORDS_COUNT_must_be_defined
; /* Cause syntax error */
`endif
module soc
#(
parameter FONT_FILE = "design/font.mem",
parameter ROM_FILE = "design/rom.mem"
)
(
input wire clock_100mhz,
output wire [17:0] sram_addr,
inout wire [15:0] sram_io,
output wire sram_cs_n,
output wire sram_oe_n,
output wire sram_we_n,
output wire vga_hs,
output wire vga_vs,
output wire [2:0] vga_red,
output wire [2:0] vga_green,
output wire [2:0] vga_blue,
input wire button1,
input wire button2,
output wire led1,
output wire led2
);
/*
* Master 0 is stack machine's wrapped data interface.
* Master 1 is stack machine's instructions interface.
*/
wire M0_ACK_I, M1_ACK_I;
wire [19:0] M0_ADR_O, M1_ADR_O;
wire [15:0] M0_DAT_I, M1_DAT_I;
wire [15:0] M0_DAT_O, M1_DAT_O;
wire M0_STB_O, M1_STB_O;
wire M0_CYC_O, M1_CYC_O;
wire M0_WE_O, M1_WE_O;
wire M0_STALL_I, M1_STALL_I;
wire S0_ACK_O, S1_ACK_O, S2_ACK_O, S3_ACK_O;
wire [17:0] S0_ADR_I, S1_ADR_I, S2_ADR_I, S3_ADR_I;
wire [15:0] S0_DAT_I, S1_DAT_I, S2_DAT_I, S3_DAT_I;
wire [15:0] S0_DAT_O, S1_DAT_O, S2_DAT_O, S3_DAT_O;
wire S0_STB_I, S1_STB_I, S2_STB_I, S3_STB_I;
wire S0_WE_I, S1_WE_I, S2_WE_I, S3_WE_I;
wire S0_STALL_O, S1_STALL_O, S2_STALL_O, S3_STALL_O;
wire CLK;
wire RST;
/* Non-wishbone */
wire M_finished;
wire clock_25mhz;
wrapped_stack_machine stack_machine
(
.CLK_I(CLK),
.RST_I(RST),
/* Instruction reading interface */
.I_ACK_I(M1_ACK_I),
.I_ADR_O(M1_ADR_O),
.I_DAT_I(M1_DAT_I),
.I_DAT_O(M1_DAT_O),
.I_STB_O(M1_STB_O),
.I_CYC_O(M1_CYC_O),
.I_WE_O(M1_WE_O),
.I_STALL_I(M1_STALL_I),
/* Data interface */
.D_ACK_I(M0_ACK_I),
.D_ADR_O(M0_ADR_O),
.D_DAT_I(M0_DAT_I),
.D_DAT_O(M0_DAT_O),
.D_STB_O(M0_STB_O),
.D_CYC_O(M0_CYC_O),
.D_WE_O(M0_WE_O),
.D_STALL_I(M0_STALL_I),
.finished(M_finished)
);
embedded_bram_slave
#(
.MEMORY_BLOCKS(1),
.WORDS_TO_INITIALIZE(`ROM_WORDS_COUNT),
.INITIAL_CONTENTS_FILE(ROM_FILE)
) slave0
(
.ACK_O(S0_ACK_O),
.CLK_I(CLK),
.ADR_I(S0_ADR_I[7:0]),
.DAT_I(S0_DAT_I),
.DAT_O(S0_DAT_O),
.RST_I(RST),
.STB_I(S0_STB_I),
.WE_I(S0_WE_I),
.STALL_O(S0_STALL_O)
);
sram_slave slave1
(
.sram_addr(sram_addr),
.sram_io(sram_io),
.sram_cs_n(sram_cs_n),
.sram_oe_n(sram_oe_n),
.sram_we_n(sram_we_n),
.ACK_O(S1_ACK_O),
.CLK_I(CLK),
.ADR_I(S1_ADR_I),
.DAT_I(S1_DAT_I),
.DAT_O(S1_DAT_O),
.RST_I(RST),
.STB_I(S1_STB_I),
.WE_I(S1_WE_I),
.STALL_O(S1_STALL_O)
);
vga
#(
.FONT_FILE(FONT_FILE)
) slave2
(
.ACK_O(S2_ACK_O),
.CLK_I(CLK),
.ADR_I(S2_ADR_I[10:0]),
.DAT_I(S2_DAT_I),
.DAT_O(S2_DAT_O),
.RST_I(RST),
.STB_I(S2_STB_I),
.WE_I(S2_WE_I),
.STALL_O(S2_STALL_O),
/* Non-wishbone */
.clock_25mhz(clock_25mhz),
.h_sync(vga_hs),
.v_sync(vga_vs),
.red(vga_red),
.green(vga_green),
.blue(vga_blue)
);
/* Slave 3 will be SPI controller, but for now - it's omitted */
assign S3_ACK_O = 1;
assign S3_DAT_O = 0;
assign S3_STALL_O = 0;
intercon intercon
(
.CLK(CLK),
.RST(RST),
.S0_ACK_O(S0_ACK_O),
.S0_ADR_I(S0_ADR_I),
.S0_DAT_I(S0_DAT_I),
.S0_DAT_O(S0_DAT_O),
.S0_STB_I(S0_STB_I),
.S0_WE_I(S0_WE_I),
.S0_STALL_O(S0_STALL_O),
.S1_ACK_O(S1_ACK_O),
.S1_ADR_I(S1_ADR_I),
.S1_DAT_I(S1_DAT_I),
.S1_DAT_O(S1_DAT_O),
.S1_STB_I(S1_STB_I),
.S1_WE_I(S1_WE_I),
.S1_STALL_O(S1_STALL_O),
.S2_ACK_O(S2_ACK_O),
.S2_ADR_I(S2_ADR_I),
.S2_DAT_I(S2_DAT_I),
.S2_DAT_O(S2_DAT_O),
.S2_STB_I(S2_STB_I),
.S2_WE_I(S2_WE_I),
.S2_STALL_O(S2_STALL_O),
.S3_ACK_O(S3_ACK_O),
.S3_ADR_I(S3_ADR_I),
.S3_DAT_I(S3_DAT_I),
.S3_DAT_O(S3_DAT_O),
.S3_STB_I(S3_STB_I),
.S3_WE_I(S3_WE_I),
.S3_STALL_O(S3_STALL_O),
.M0_ACK_I(M0_ACK_I),
.M0_ADR_O(M0_ADR_O),
.M0_DAT_I(M0_DAT_I),
.M0_DAT_O(M0_DAT_O),
.M0_STB_O(M0_STB_O),
.M0_CYC_O(M0_CYC_O),
.M0_WE_O(M0_WE_O),
.M0_STALL_I(M0_STALL_I),
.M1_ACK_I(M1_ACK_I),
.M1_ADR_O(M1_ADR_O),
.M1_DAT_I(M1_DAT_I),
.M1_DAT_O(M1_DAT_O),
.M1_STB_O(M1_STB_O),
.M1_CYC_O(M1_CYC_O),
.M1_WE_O(M1_WE_O),
.M1_STALL_I(M1_STALL_I)
);
reg [2:0] clock_divider;
always @ (posedge clock_100mhz)
clock_divider <= clock_divider + 1;
assign clock_25mhz = clock_divider[1];
/* We might later raise it up to even as high as 50 MHz */
assign CLK = clock_divider[2];
reg reset;
always @ (posedge CLK)
reset <= !button1;
assign RST = reset;
assign led1 = !M_finished;
assign led2 = !M_finished;
`ifdef SIMULATION
/* avoid undefined values */
initial begin
clock_divider <= 0;
reset <= 1;
end
`endif
endmodule // soc
|
