cocotb: Try to run quickstart

Passes both using SIM=verilator and SIM=icarus

4 files changed, 65 insertions, 0 deletions

diff --git a/cocotb_try/.gitignore b/cocotb_try/.gitignore
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+++ b/cocotb_try/.gitignore
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+sim_build/
+__pycache__/
+results.xml
diff --git a/cocotb_try/Makefile b/cocotb_try/Makefile
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+++ b/cocotb_try/Makefile
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+# Makefile
+
+# defaults
+SIM ?= verilator
+TOPLEVEL_LANG ?= verilog
+
+VERILOG_SOURCES += $(PWD)/my_design.sv
+# use VHDL_SOURCES for VHDL files
+
+# TOPLEVEL is the name of the toplevel module in your Verilog or VHDL file
+TOPLEVEL = my_design
+
+# MODULE is the basename of the Python test file
+MODULE = test_my_design
+
+# include cocotb's make rules to take care of the simulator setup
+include $(shell cocotb-config --makefiles)/Makefile.sim
+
diff --git a/cocotb_try/my_design.sv b/cocotb_try/my_design.sv
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+++ b/cocotb_try/my_design.sv
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+// This file is public domain, it can be freely copied without restrictions.
+// SPDX-License-Identifier: CC0-1.0
+
+module my_design(input logic clk);
+
+  timeunit 1ns;
+  timeprecision 1ns;
+
+  logic my_signal_1;
+  logic my_signal_2;
+
+  assign my_signal_1 = 1'bx;
+  assign my_signal_2 = 0;
+
+endmodule
diff --git a/cocotb_try/test_my_design.py b/cocotb_try/test_my_design.py
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+++ b/cocotb_try/test_my_design.py
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+
+# https://docs.cocotb.org/en/stable/quickstart.html
+# test_my_design.py (extended)
+
+import cocotb
+from cocotb.triggers import FallingEdge, Timer
+
+
+async def generate_clock(dut):
+    """Generate clock pulses."""
+
+    for cycle in range(10):
+        dut.clk.value = 0
+        await Timer(1, units="ns")
+        dut.clk.value = 1
+        await Timer(1, units="ns")
+
+
+@cocotb.test()
+async def my_second_test(dut):
+    """Try accessing the design."""
+
+    await cocotb.start(generate_clock(dut))  # run the clock "in the background"
+
+    await Timer(5, units="ns")  # wait a bit
+    await FallingEdge(dut.clk)  # wait for falling edge/"negedge"
+
+    dut._log.info("my_signal_1 is %s", dut.my_signal_1.value)
+    assert dut.my_signal_2.value[0] == 0, "my_signal_2[0] is not 0!"