(r1) ExtendedHwFunctions < P1076

P1076 Web>Vhdl2019CollectedRequirements>ExtendedHwFunctions (revision 1) (raw view)~~EditAttach~~
---+ Extended Hardware functions like mux, decoders, adders

<br />%TOC%

---++ Proposal Editing Information
   * Who Updates:
   * Date Proposed:
   * Date Last Updated:
   * Priority:
   * Complexity:
   * Focus: Testbench
---++ Requirement Summary
   * Simplify Creation of RTL macros (Also interested: Main.MartinThompson, Main.DanielKho):
   * Library of standard functions
      * Mux2, what else?
         * To what use, Jim says behavior, David K. suggests mixed level of abstraction, retargetting
   * Syntax based flip-flop extensions are here: [[ClockedShorthand]]

See also: [[MeetingDecember15][Dec 15, 2011]] and [[MeetingMarch31][Mar 31, 2011]]
---++ Proposal

Recommend that we forward this to the open source package working group for implementation separate of the VHDL standard.

Create hardware with procedure and function calls. For example, use a procedure for a flip-flop:

Reg(Clk, D, Q) ;

RegPipe (Clk, D, Q, 5) ; -- adds a 5 deep pipelining / shift register.

---++ Rationale

---++ Related and/or Competing Issues: None

---++ Use Model:

---++ Questions

---++ General Comments

The open source and vendor independet IP core library [[https://github.com/VLSI-EDA/PoC][PoC]] comes with several syntheziable functions.<br />Examples for one-liners:
   * a D-FF in standard VHDL<br /><span class="WYSIWYG_TT">mySignal_reg &lt;= mySignal when rising_edge(Clock);</span>
   * a D-FF with enable and reset, as well as a reset value (INIT)<br /><span class="WYSIWYG_TT">mySignal_reg &lt;= ffdre(q =&gt; mySignal_reg, d =&gt; mySignal, en =&gt; enable, rst =&gt; reset, INIT =&gt; '1') when rising_edge(Clock);</span>
   * an optional output register<br /><span class="WYSIWYG_TT">output &lt;= output_i when registered(Clock, IS_REGISTERED);</span>
   * Encoding conversion<br /><span class="WYSIWYG_TT">gray &lt;= bin2gray(Counter);</span><br /><span class="WYSIWYG_TT">onehot &lt;= bin2onehot(Counter);</span>

Source: [[https://github.com/VLSI-EDA/PoC/blob/master/src/common/components.vhdl][PoC.components]] and [[https://github.com/VLSI-EDA/PoC/blob/master/src/common/utils.vhdl][PoC.utils]]

-- Main.PatrickLehmann - 2016-02-
---++ Supporters

_Add your signature here to indicate your support for the proposal_

<em>-- Main.MartinThompson - 2013-02-22<br /></em>

-- Main.PatrickLehmann - 2016-02-19
Topic revision: r1 - 2020-02-17 - 15:34:30 - TWikiGuest
P1076