add tut3 folder, shift register code works

.gitignore

@@ -1,6 +1,4 @@
-*/obj_dir
 */build
-*/*.bin
-*/*.asc
-*/*.json
+*/obj_dir
+*/diagram
 

fsm/Makefile

@@ -0,0 +1,56 @@
+SIM_TARGET = build/top
+BIN_TARGET = build/top.bin
+PCF = constraints/iceFUN.pcf
+TIMING = constraints/timing.py
+YOSYS = yosys
+PNR = nextpnr-ice40
+IPACK = icepack
+BURN = iceFUNprog
+
+VERILATOR=verilator
+VERILATOR_ROOT ?= $(shell bash -c 'verilator -V|grep VERILATOR_ROOT | head -1 | sed -e "s/^.*=\s*//"')
+VINC := $(VERILATOR_ROOT)/include
+
+RTL_SRC := $(wildcard rtl/*.v)
+SIM_SRC := $(wildcard sim/*.cc)
+BUILD_DIR := ./build
+
+.PHONY: all burn
+all: $(SIM_TARGET)  $(BIN_TARGET)
+
+# -GWIDTH=5 allows passing parameter to verilog module
+$(BUILD_DIR)/Vtop.cc: $(RTL_SRC)
+	@echo "Running verilator"
+	@mkdir -p $(BUILD_DIR)
+	@$(VERILATOR) --trace -Wall -GWIDTH=10 -cc $^ --top-module top\
+		--Mdir $(BUILD_DIR) --timescale-override 10ns/1ns
+
+$(BUILD_DIR)/Vtop__ALL.a: $(BUILD_DIR)/Vtop.cc
+	@make --no-print-directory -C $(BUILD_DIR) -f Vtop.mk
+
+# std=c++11 flag is needed as of verilator v4.100
+$(SIM_TARGET): $(SIM_SRC) $(BUILD_DIR)/Vtop__ALL.a
+	@echo "Compiling simulation executable"
+	@g++ -I$(VINC) -I$(BUILD_DIR) -std=c++14 $(VINC)/verilated.cpp\
+		$(VINC)/verilated_vcd_c.cpp $^ -o $@
+	@echo "Run simulation with ./$(SIM_TARGET)"
+
+$(BUILD_DIR)/top.json: $(RTL_SRC)
+	@echo "Synthesizing ..."
+	@mkdir -p $(BUILD_DIR)
+	@$(YOSYS) -p "synth_ice40 -top top -json build/top.json" -q $^
+
+$(BIN_TARGET): $(BUILD_DIR)/top.json $(PCF) $(TIMING)
+	@echo "Routing and building binary stream ..."
+	@$(PNR) -r --hx8k --json $< --package cb132 \
+		--asc $(BUILD_DIR)/top.asc --opt-timing --pcf $(PCF) \
+		--pre-pack $(TIMING) -l $(BUILD_DIR)/pnr_report.txt -q 
+	@$(IPACK) $(BUILD_DIR)/top.asc $@
+	@echo "Done!"
+
+burn: $(BIN_TARGET)
+	@$(BURN) $<
+
+.PHONY: clean
+clean:
+	rm -rf $(BUILD_DIR)

fsm/constraints/iceFUN.pcf

@@ -0,0 +1,12 @@
+# For iceFUN board
+
+set_io --warn-no-port i_clk  	P7
+set_io --warn-no-port lcol1	A12
+set_io --warn-no-port o_led[0] 	C10
+set_io --warn-no-port o_led[1] 	A10
+set_io --warn-no-port o_led[2] 	D7
+set_io --warn-no-port o_led[3] 	D6
+set_io --warn-no-port o_led[4] 	A7
+set_io --warn-no-port o_led[5] 	C7
+set_io --warn-no-port o_led[6] 	A4
+set_io --warn-no-port o_led[7] 	C4

fsm/constraints/timing.py

@@ -0,0 +1 @@
+ctx.addClock("i_clk", 100)

fsm/rtl/clk_gen.v

@@ -0,0 +1,13 @@
+`default_nettype none
+// dummy clock generator, should be replaced by a PLL clock gen eventually
+module clk_gen(
+   input wire i_clk,
+   output wire o_clk
+);
+
+assign o_clk = i_clk;
+
+endmodule
+// Local Variables:
+// verilog-library-directories:(".." "./rtl" ".")
+// End:

fsm/rtl/top.v

@@ -0,0 +1,42 @@
+`default_nettype  none
+
+module top(i_clk, o_led, lcol1);
+   parameter WIDTH = 22;
+   input wire i_clk;
+   output reg [7:0] o_led;
+   output wire lcol1;
+
+   wire clk_12MHz;
+
+   clk_gen clk_gen_0 (/*autoinst*/
+      // Outputs
+      .o_clk                 (clk_12MHz),
+      // Inputs
+      .i_clk                 (i_clk));
+
+   reg [WIDTH-1:0] counter;
+   reg [7:0] obuf; // output buffer, take into account the icefun use active low LED
+   reg strobe;
+
+   initial begin
+      obuf = 8'h1;
+      {strobe, counter} = 0;
+   end
+
+   always @(posedge clk_12MHz)
+      {strobe, counter} <= counter + 1'b1;
+
+   // shifting bit, to the left
+   always @(posedge clk_12MHz)
+      if (strobe)
+         obuf <= {obuf[6:0], obuf[7]};
+
+   always @(*)
+      o_led = ~obuf;
+
+   assign lcol1 = 1'b0;
+endmodule
+
+// Local Variables:
+// verilog-library-directories:(".." "./rtl" ".")
+// End:

fsm/sim/top.cc

@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "verilated.h"
+#include "verilated_vcd_c.h"
+#include "Vtop.h"
+
+void	tick(int tickcount, Vtop *tb, VerilatedVcdC* tfp) {
+	tb->eval();
+	if (tfp)
+		tfp->dump(tickcount * 10 - 2);
+	tb->i_clk = 1;
+	tb->eval();
+	if (tfp)
+		tfp->dump(tickcount * 10);
+	tb->i_clk = 0;
+	tb->eval();
+	if (tfp) {
+		tfp->dump(tickcount * 10 + 5);
+		tfp->flush();
+	}
+}
+
+int main(int argc, char **argv) {
+	// Call commandArgs first!
+	Verilated::commandArgs(argc, argv);
+
+	// Instantiate our design
+	Vtop *tb = new Vtop;
+	Verilated::traceEverOn(true);
+	VerilatedVcdC* tfp = new VerilatedVcdC;
+
+	tb->trace(tfp, 00);
+	tfp->open("build/waveform.vcd");
+
+	unsigned tickcount = 0;
+  int last_led = tb->o_led;
+
+	for(int k=0; k<(1 << 12); k++) {
+    tick(++tickcount, tb, tfp);
+
+    if (last_led != tb->o_led) {
+      printf("k = %7d, led = %d\n", k, tb->o_led);
+    }
+
+    last_led = tb->o_led;
+	}
+}