# VHDL Ref — VHDL, Verilog, SystemVerilog

> VHDL and Verilog hardware description language reference with examples and search. (iPhone/iPad app by squishLogic.)

- Source: https://appshunter.io/ios/app/vhdl-ref/id418473744 (this page in markdown: same URL + `.md`)
- Developer: [squishLogic](https://appshunter.io/developer/353387502)
- Category: Reference, Utilities
- Price: $2.99
- Rating: 3.20/5 from 5 App Store ratings · 8 written reviews indexed
- Age rating: 4+
- Requires: iOS 18.6 · 1 MB
- Languages: American English
- Released: 2011-02-10
- Data updated: 2026-09-03
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/vhdl-ref/id418473744/reviews.md

## What is VHDL Ref?

The pocket translator for hardware description languages. VHDL Ref is a quick reference for VHDL, Verilog, and SystemVerilog, written by engineers for engineers. For every construct in VHDL it shows the equivalent in Verilog, and vice versa.

Whether you are an FPGA or ASIC designer who thinks in one language but has to read the other, a verification engineer working in SystemVerilog, or an engineering student in your first digital design course, VHDL Ref puts the answer one tap away.

+ 328 entries covering every keyword, operator, and data type in both languages
+ Cross-language equivalents on every entry: see how the other language says it
+ A simple worked example for every single entry
+ SystemVerilog coverage, plus VHDL 2008 and Verilog 2001 notation
+ All pre-defined VHDL attributes
+ All Verilog primitive gates and drive strengths
+ Filter by language and by element type
+ Works completely offline: in the lab, on a plane, behind the firewall
+ No ads, no subscription, no account, no tracking

Native on iPhone, iPad, and Mac (a real Mac app, not a port), so the same reference sits next to your simulator at your desk and rides in your pocket everywhere else.

Note: VHDL Ref is a reference, not a simulator or compiler. It is the book you keep open beside your tools, rebuilt for the device you always have with you.

## Key features

- Searchable dictionary of keywords, operators, and data types
- Examples for every reference construct
- Common functions for VHDL and Verilog
- Pre-defined attributes for VHDL
- Primitive gates and drive strengths for Verilog
- Filter by language (VHDL, Verilog, or both)
- Filter by language elements

## Recent user reviews (8 of 8)

All indexed reviews: https://appshunter.io/ios/app/vhdl-ref/id418473744/reviews.md

### 1/5 — There’s no there there.

*2020-08-04*

Minimal info in each definition. Examples not elaborated. Practically useless app. Very little real work put into this. Barely worth 3 cents, certainly not worth $3.

### 3/5 — Ziemlich gut

*2019-01-08*

Sicher eine vollständige Befehls-Synopsis, aber mehr auch nicht. Einen Punkt ziehe ich ab, weil nur Hochformat möglich ist, auf dem iPad unbequem, den anderen für die nervige Umblätter-Animation.

### 4/5 — Good reference

*2017-09-19*

It's a good reference guide, but as one if the previous reviewers said, when you scroll all the way down, the last 2 options are behind the filter bar. It prevents me from choosing them. Please fix this. I would have given the app 5 stars

### 1/5 — Value

*2015-03-18*

Pretty useless.

### 5/5 — Want More....

*2015-01-11*

I find this to be a very useful app. Works well for a reference for VHDL (Verilog too, but I've used that less).
I would like to see detailed examples, especially some examples converting between VHDL and Verilog. Also, maybe some test benches.

### 3/5 — Learning Verilog

*2013-06-16*

This looked like the best of the three I looked at. Good little reference for the keywords and operators. There is a problem with the list though. When scrolling all the way to the bottom there are four table items that are hidden behind the lower bar with the filter button on it. I can scroll them up and see them but cannot select them since the table snaps back down. iPhone 4S. Seems like it was made for the iPhone 5 screen. Please fix to auto screen size.

### 5/5 — Engineer

*2013-03-10*

Snappy and concise.  Easy to zero in on the needed term.  I like the consolidation of the many related VHDL terms.  Excellent reference!

### 1/5 — Useless

*2011-04-19*

Too basic, lack of lot of information, i.e. entity is just a small description and do not contain full information/construction/specification

i.e.
entity entity_name is [generic generic_declarations);] ...

just say entity is blabla and useless example.

Also lacks links between definitions, i.e. 
Example:
entity...
 generic <- do not have a link, so you have to search for that

## Frequently asked questions about VHDL Ref

### What is VHDL Ref?

VHDL Ref is a reference manual for the Hardware Description Languages VHDL and Verilog. It provides a searchable dictionary of language elements, examples, and common functions for both languages.

### Who is VHDL Ref designed for?

VHDL Ref is designed for experienced custom digital logic designers working with FPGAs or ASICs, as well as electrical engineering students learning these languages.

### What languages does VHDL Ref cover?

VHDL Ref covers VHDL and Verilog, including SystemVerilog. It offers cross-language comparisons for every construct.

### Does VHDL Ref have ads?

No, VHDL Ref does not contain advertisements. It is a paid application with no ads.

### What is the price of VHDL Ref?

VHDL Ref is available for a one-time purchase of $2.99.

### On what devices can I use VHDL Ref?

VHDL Ref is supported on iPhone and iPad devices.

### How often is VHDL Ref updated?

The latest version of VHDL Ref is 3.1, last updated on February 9, 2026. The app was initially released on February 10, 2011.

### What is the user rating for VHDL Ref?

VHDL Ref has a rating of 3.2 stars based on 5 ratings.

## Version history (last 5 releases)

### 3.2 — 2026-08-31

Fixed availability on the Mac App Store.
Corrected element categories for nor, rol, ror, reg, wire, and integer.
Every entry now shows a consistent VHDL/Verilog/SystemVerilog version label.
Keywords shared by both languages now show each language's definition separately.
General corrections and typo fixes throughout.

### 3.1 — 2026-02-09

+ Add SystemVerilog
+ More accurate cross-language equivlants
+ Fix bug with displaying reserved words that appear in both languages.

### 3.0 — 2026-02-08

+ Add support for Mac OS
+ Add VHDL 2008 reserved words

### 2.2 — 2026-01-27

+ Highlight keyword wherever it appears in example
+ Other keywords in definition are now links
+ Add VHDL protected keyword
+ Simply filter, changes take effect immediatlely

### 2.1 — 2023-05-22

Minor update for new iOS.

## Apps similar to VHDL Ref

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-03.*