basic_verilog/README.md

Must-have verilog systemverilog modules
=======================================
Originally published as part of https://github.com/pConst/basic_verilog   
by Konstantin Pavlov, pavlovconst@gmail.com   

Hi! This is a collection of Verilog SystemVerilog synthesizable modules.   

All the code is highly reusable across typical FPGA projects and mainstream FPGA vendors.   

Please feel free to make pull requests or contact me in case you spot any code issues.   

Also, give me a pleasure, tell me if the code has got succesfully implemented in your hobby, scientific or industrial projects!   
   
Licensing
---------
The code is licensed under CC BY-SA 4_0   
That means, that you can remix, transform, and build upon the material for any purpose, even commercially.   
However, YOU MUST provide the name of the creator and distribute your contributions under the same license as the original.   
   
Contents description
--------------------
For your convinience I`ve tagged some sources by their "difficulty":   
:green_circle: - for the most basic tasks   
:red_circle: - for advanced or special purpose routines   
   
If you are a beginner in HW design - you may want to start exploring :green_circle: code first.   
Almost every source file in the repository contains detailed description and instantiation template!   
   
| USAGE         | DIRECTORY    | DESCRIPTION |
|---------------|--------------|-------------|
|               | Advanced Synthesis Cookbook/ | useful code from Altera's cookbook |
|               | KCPSM6_Release9_30Sept14/ | Xilinx's Picoblaze soft processor sources |
| :red_circle:  | XilinxBoardStore_with_Alveo_cards_support | board definitions for Xilinx Alveo accelerator cards |
|               | pacoblaze-2.2/ | version of Picoblaze adapted for Altera devices |
|               | avalon_mm_master_templates/ | Avalon-MM component templates from Altera |
|               | axi_master_slave_templates/ | AXI componet templates generated by Vivado |
|               | benchmark_projects/ | benchmarking various IDEs to compile exact same Verilog project |
|               | dual_port_ram_templates/ | Block RAM templates |
|               | example_projects/ | FPGA project boilerplates and examples |
|               | gitignores/ | gitignore files for FPGA projects |
|               | scripts/ | useful TCL, batch and shell scripts |
| :red_circle:  | scripts_for_intel_hls/ | useful scripts for compiling for Intel HLS |
| :red_circle:  | scripts_for_xilinx_hls/ | useful scripts for compiling for Xilinx HLS |
|               | xpm | Xilinx parametrizable macros sources |
   
| USAGE          | FILE               | DESCRIPTION |
|----------------|--------------------|-------------|
|                | adder_tree.sv      | adding multiple values together in parallel |
|                | axi4l_logger.sv    |  |
| :green_circle: | bin2gray.sv        | combinational Gray code to binary converter |
|                | bin2pos.sv         | converts binary coded value to positional (one-hot) code |
|                | cdc_data.sv        |  |
|                | cdc_strobe.sv      |  |
| :green_circle: | clk_divider.sv     | wide reference clock divider |
|                | clogb2.svh         |  |
| :green_circle: | debounce.v         | two-cycle debounce for input buttons |
| :green_circle: | delay.sv           | useful module to make static delays or to synchronize across clock domains |
|                | delayed_event.sv   |  |
|                | dynamic_delay.sv   | dynamic delay for arbitrary input signal |
| :green_circle: | edge_detect.sv     | combinational edge detector, gives one-tick pulses on every signal edge |
|                | encoder.v          | digital encoder input logic module |
| :red_circle:   | fast_counter.sv    |  |
|                | fifo_combiner.sv   |  |
|                | fifo_operator.sv   |  |
| :red_circle:   | fifo_single_clock_ram_*.sv | single-clock FIFO buffer (queue) implementation |
| :red_circle:   | fifo_single_clock_reg_*.sv | single-clock FIFO buffer (queue) implementation |
| :green_circle: | gray2bin.sv        | combinational binary to Gray code converter |
| :red_circle:   | gray_functions.vh  |  |
| :green_circle: | hex2ascii.sv       |  |
|                | leave_one_hot.sv   | combinational module that leaves only lowest hot bit |
|                | lifo.sv            | single-clock LIFO buffer (stack) implementation |
|                | main_tb.sv         | basic testbench template |
|                | moving_average.sv  |  |
|                | pack_unpack_array.v |  |
|                | pattern_detect.sv  |  |
|                | pdm_modulator.sv   |  |
|                | pos2bin.sv         | converts positional (one-hot) value to binary representation |
|                | prbs_gen_chk.sv    | PRBS pattern generator or checker |
|                | preview_fifo.sv    |  |
|                | priority_enc.sv    |  |
|                | pulse_gen.sv       | generates pulses with given width and delay |
|                | pulse_stretch.sv   | configurable pulse stretcher/extender module |
|                | pwm_modulator.sv   |  |
| :red_circle:   | read_ahead_buf.sv  |  |
|                | reset_set.sv       | SR trigger variant w/o metastable state, set dominates here |
|                | reset_set_comb.sv  |  |
|                | reverse_bytes.sv   | reverses bytes order within multi-byte array |
|                | reverse_dimensions.sv |  |
|                | reverse_vector.sv  | reverses signal order within multi-bit bus |
|                | round_robin_enc.sv |  |
|                | round_robin_performance_enc.sv |  |
|                | set_reset.sv       | SR trigger variant w/o metastable state, reset dominates here |
|                | set_reset_comb.sv  |  |
|                | sim_clk_gen.sv     |  |
| :red_circle:   | soft_latch.sv      |  |
|                | spi_master.sv      | universal spi master module |
| :red_circle:   | true_dual_port_write_first_2_clock_ram.sv |  |
| :red_circle:   | true_single_port_write_first_ram.sv |  |
|                | uart_debug_printer.sv |  |
| :green_circle: | uart_rx.sv         | straightforward yet simple UART receiver |
|                | uart_rx_shifter.sv | UART-like receiver shifter for simple synchronous messaging inside the FPGA or between FPGAs |
| :green_circle: | uart_tx.sv         | straightforward yet simple UART transmitter |
|                | uart_tx_shifter.sv | UART-like transmitter shifter for simple synchronous messaging inside the FPGA or between FPGAs |
   
Also added testbenches for selected modules.