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| -rw-r--r-- | LICENSE | 29 | ||||
| -rw-r--r-- | README.md | 14 | ||||
| -rw-r--r-- | src/rtl/toggle.v | 92 | ||||
| -rw-r--r-- | src/tb/tb_toggle.v | 110 | ||||
| -rwxr-xr-x | toolruns/Makefile | 79 |
5 files changed, 324 insertions, 0 deletions
@@ -0,0 +1,29 @@ +Author: Joachim Strömbergson +Copyright (c) 2014, NORDUnet A/S +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: +- Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + +- Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + +- Neither the name of the NORDUnet nor the names of its contributors may + be used to endorse or promote products derived from this software + without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED +TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/README.md b/README.md new file mode 100644 index 0000000..b2c0d35 --- /dev/null +++ b/README.md @@ -0,0 +1,14 @@ +toggle +====== +## Introduction ## + +This repo contains a simple deign that toggles an ouput pin. The toggle +is in sync with the given sys_clk, but the toggle circuit divides down +the clock. The divisor is build time defined. + +The design is used in the Cryptech FPGA design to observe internal +clock frequencies. + + +## Status ## +Has been simulated with Icarus Verilog. diff --git a/src/rtl/toggle.v b/src/rtl/toggle.v new file mode 100644 index 0000000..548b85e --- /dev/null +++ b/src/rtl/toggle.v @@ -0,0 +1,92 @@ +//====================================================================== +// +// toggle +// ------ +// gpio pin toggler. +// +// +// Author: Joachim Strombergson +// Copyright (c) 2018, NORDUnet A/S +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// - Redistributions of source code must retain the above copyright notice, +// this list of conditions and the following disclaimer. +// +// - Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in the +// documentation and/or other materials provided with the distribution. +// +// - Neither the name of the NORDUnet nor the names of its contributors may +// be used to endorse or promote products derived from this software +// without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED +// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// +//====================================================================== + +module toggle + + ( + input wire sys_clk, + input wire reset_n, + output wire [7 : 0] gpio_b + ); + + localparam TOGGLE_DELAY_CYCLES = 100; + + reg [7 : 0] toggle_ctr_reg; + reg [7 : 0] toggle_ctr_new; + + reg toggle_reg; + reg toggle_we; + + assign gpio_b = {7'b1010101, toggle_reg}; + + always @(posedge sys_clk) + begin: sys_clk_toggle_reg_update + if (!reset_n) + begin + toggle_ctr_reg <= 32'h0; + toggle_reg <= 1'b0; + end + else + begin + toggle_ctr_reg <= toggle_ctr_new; + + if (toggle_we) + toggle_reg <= ~toggle_reg; + end + end + + always @* + begin : sys_clk_toggle + if (toggle_ctr_reg == TOGGLE_DELAY_CYCLES) + begin + toggle_ctr_new = 32'h0; + toggle_we = 1'b1; + end + else + begin + toggle_ctr_new = toggle_ctr_reg + 1'b1; + toggle_we = 1'b0; + end + end + +endmodule // toggle + +//====================================================================== +// EOF toggle.v +//====================================================================== diff --git a/src/tb/tb_toggle.v b/src/tb/tb_toggle.v new file mode 100644 index 0000000..0f3a9ad --- /dev/null +++ b/src/tb/tb_toggle.v @@ -0,0 +1,110 @@ +//====================================================================== +// +// tb_toggle +// --------- +// Testbench for the gpio pin toggler. +// +// +// Author: Joachim Strombergson +// Copyright (c) 2018, NORDUnet A/S +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// - Redistributions of source code must retain the above copyright notice, +// this list of conditions and the following disclaimer. +// +// - Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in the +// documentation and/or other materials provided with the distribution. +// +// - Neither the name of the NORDUnet nor the names of its contributors may +// be used to endorse or promote products derived from this software +// without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED +// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// +//====================================================================== + +module tb_toggle(); + + parameter CLK_HALF_PERIOD = 1; + parameter CLK_PERIOD = 2 * CLK_HALF_PERIOD; + + reg tb_sys_clk; + reg tb_reset_n; + wire [7 : 0] tb_gpio_b; + reg [31 : 0] cycle_ctr; + + toggle dut( + .sys_clk(tb_sys_clk), + .reset_n(tb_reset_n), + .gpio_b(tb_gpio_b) + ); + + + //---------------------------------------------------------------- + // clk_gen + // + // Always running clock generator process. + //---------------------------------------------------------------- + always + begin : clk_gen + #CLK_HALF_PERIOD; + tb_sys_clk = !tb_sys_clk; + end // clk_gen + + + //---------------------------------------------------------------- + // sys_monitor() + // + // An always running process that creates a cycle counter and + // conditionally displays information about the DUT. + //---------------------------------------------------------------- + always + begin : sys_monitor + cycle_ctr = cycle_ctr + 1; + + #(CLK_PERIOD); + + $display("cycle: 0x%016x gpio_b: 0x%08x toggle_ctr: 0x%08x toggle_reg: 0x%01x", + cycle_ctr, tb_gpio_b, dut.toggle_ctr_reg, dut.toggle_reg); + end + + + //---------------------------------------------------------------- + // init_sim() + // + // Initialize all counters and testbed functionality as well + // as setting the DUT inputs to defined values. + //---------------------------------------------------------------- + initial + begin + cycle_ctr = 0; + tb_sys_clk = 0; + tb_reset_n = 0; + + #(CLK_PERIOD * 10); + + tb_reset_n = 1; + + #(CLK_PERIOD * 10000); + $finish; + end + +endmodule // tb_toggle + +//====================================================================== +// EOF tb_toggle.v +//====================================================================== diff --git a/toolruns/Makefile b/toolruns/Makefile new file mode 100755 index 0000000..1bd9c87 --- /dev/null +++ b/toolruns/Makefile @@ -0,0 +1,79 @@ +#=================================================================== +# +# Makefile +# -------- +# Makefile for building the toggle design and simulation. +# +# +# Author: Joachim Strombergson +# Copyright (c) 2018, NORDUnet A/S +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# - Redistributions of source code must retain the above copyright notice, +# this list of conditions and the following disclaimer. +# +# - Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# - Neither the name of the NORDUnet nor the names of its contributors may +# be used to endorse or promote products derived from this software +# without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +# IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED +# TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +# +#=================================================================== + +TOGGLE_SRC =../src/rtl/toggle.v +TB_TOGGLE_SRC =../src/tb/tb_toggle.v + +CC = iverilog +CC_FLAGS = -Wall + +LINT = verilator +LINT_FLAGS = +1364-2001ext+ --lint-only -Wall -Wno-fatal -Wno-DECLFILENAME + +all: top.sim + + +top.sim: $(TB_TOGGLE SRC) $(TOGGLE_SRC) + $(CC) $(CC_FLAGS) -o top.sim $(TB_TOGGLE_SRC) $(TOGGLE_SRC) + + +sim-top: top.sim + ./top.sim + + +lint: $(TOP_SRC) + $(LINT) $(LINT_FLAGS) $(TOGGLE_SRC) + + +clean: + rm -f top.sim + + +help: + @echo "Supported targets:" + @echo "------------------" + @echo "all: Build all simulation targets." + @echo "lint: Lint all rtl source files." + @echo "top.sim: Build top level simulation target." + @echo "sim-top: Run top level simulation." + @echo "clean: Delete all built files." + +#=================================================================== +# EOF Makefile +#=================================================================== |