| /* |
| * StriVe - A full example SoC using PicoRV32 in SkyWater s8 |
| * |
| * Copyright (C) 2017 Clifford Wolf <clifford@clifford.at> |
| * Copyright (C) 2018 Tim Edwards <tim@efabless.com> |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| * |
| */ |
| |
| `timescale 1 ns / 1 ps |
| |
| `include "caravel.v" |
| `include "spiflash.v" |
| `include "tbuart.v" |
| |
| module uart_tb; |
| reg clock; |
| |
| reg SDI, CSB, SCK, RSTB; |
| |
| wire [1:0] gpio; |
| wire flash_csb; |
| wire flash_clk; |
| wire flash_io0; |
| wire flash_io1; |
| wire flash_io2; |
| wire flash_io3; |
| wire SDO; |
| |
| always #12.5 clock <= (clock === 1'b0); |
| |
| initial begin |
| clock = 0; |
| end |
| |
| initial begin |
| $dumpfile("uart.vcd"); |
| $dumpvars(0, uart_tb); |
| |
| $display("Wait for UART o/p"); |
| repeat (150) begin |
| repeat (10000) @(posedge XCLK); |
| // Diagnostic. . . interrupts output pattern. |
| end |
| $finish; |
| end |
| |
| initial begin |
| CSB <= 1'b1; |
| SCK <= 1'b0; |
| SDI <= 1'b0; |
| RSTB <= 1'b0; |
| #1000; |
| RSTB <= 1'b1; // Release reset |
| #2000; |
| CSB <= 1'b0; |
| end |
| |
| always @(gpio) begin |
| if(gpio == 16'hA000) begin |
| $display("UART Test started"); |
| end |
| else if(gpio == 16'hAB00) begin |
| #1000; |
| $finish; |
| end |
| end |
| |
| wire VDD3V3; |
| wire VDD1V8; |
| wire VSS; |
| |
| assign VSS = 1'b0; |
| assign VDD1V8 = 1'b1; |
| assign VDD3V3 = 1'b1; |
| |
| caravel uut ( |
| .vdd3v3 (VDD3V3), |
| .vdd1v8 (VDD1V8), |
| .vss (VSS), |
| .clock (clock), |
| .SDI (SDI), |
| .SDO (SDO), |
| .CSB (CSB), |
| .SCK (SCK), |
| .ser_rx (1'b0), |
| .ser_tx (tbuart_rx), |
| .irq (1'b0), |
| .gpio (gpio), |
| .flash_csb(flash_csb), |
| .flash_clk(flash_clk), |
| .flash_io0(flash_io0), |
| .flash_io1(flash_io1), |
| .flash_io2(flash_io2), |
| .flash_io3(flash_io3), |
| .RSTB (RSTB) |
| ); |
| |
| spiflash #( |
| .FILENAME("uart.hex") |
| ) spiflash ( |
| .csb(flash_csb), |
| .clk(flash_clk), |
| .io0(flash_io0), |
| .io1(flash_io1), |
| .io2(flash_io2), |
| .io3(flash_io3) |
| ); |
| |
| // Testbench UART |
| tbuart tbuart ( |
| .ser_rx(tbuart_rx) |
| ); |
| |
| endmodule |