Welcome to icestudio’s documentation!¶
Icestudio is a graphic IDE for open FPGAs. It is built on top of the Icestorm project. This IDE is available for GNU/Linux, Windows and Mac OS X.
Supported boards:
- IceZUM Alhambra
- Kéfir I iCE40-HX4K
- Nandland Go board
- iCE40-HX8K Breakout Board
- iCEstick Evaluation Kit
- icoBOARD 1.0
Source code: https://github.com/FPGAwars/icestudio
Installation¶
GNU/Linux¶
- Install Python 2.7 and xclip (to enable Copy/Paste).
- Download the AppImage file and make it executable:
$ chmod a+x icestudio-0.3.1*.AppImage
Hint
You can download the ZIP release and install it in the system using the script linux_installer.sh. This script registers the .ice files as Icestudio project. There is also a linux_uninstaller.sh to revert the previous configuration.
Windows¶
- Download and execute the Windows installer.
Note
Python 2.7 will be installed automatically if it is not installed. This installer registers the .ice files as Icestudio project.
Warning
If the error Failed building wheel for apio [...] appears pip installer may be blocked. Disable the antivirus and try again.
Quick Start¶
Setup the toolchain¶
Go to Tools > Toolchain > Install
Apio backend and all its needed packages will be installed. This operation does not require Internet connection.
Setup the drivers¶
Connect your FPGA board and select Tools > Drivers > Enable. This operation requires administrator privileges.
Note
In Windows, an external application (Zadig) is launched to replace the existing FTDI driver of the Interface 0 by libusbK.
In MacOS this operation requires Internet connection to allow Homebrew to install libffi and libftdi packages.
Upload a design¶
Go to Select > Board > IceZUM Alhambra
Go to File > Examples > 1. Basic > 01. One LED
Then, you can verify, build or upload the project in Tools > Verify | Build | Upload.
Here is the FPGA board with the LED0 turned on.
User Guide¶
Menu¶
File¶
| Action | Description | Shorcuts | Mac OS |
|---|---|---|---|
| New | Create a new window | Ctrl+N | ⌘+N |
| Open... | Open a project | Ctrl+O | ⌘+O |
| Blocks | Show the selected blocks | ||
| Examples | Show the selected examples | ||
| Add as block... | Add a project as a block | ||
| Save | Save the current project | Ctrl+S | ⌘+S |
| Save as... | Save the current with a new name | Ctrl+Shift+S | Shift+⌘+S |
| Export... | Export multiple output files | ||
| Quit | Close the application | Ctrl+Q | ⌘+Q |
Note
The exportable files are: Verilog, PCF, Testbench, GTKWave, BLIF, ASC and Bitstream
Edit¶
| Action | Description | Shortcut | Mac OS |
|---|---|---|---|
| Redo | Revert the last undo | Ctrl+Y | Ctrl+Shift+Z | ⌘+Y | Shift+⌘+Z |
| Cut | Cut selected blocks | Ctrl+X | ⌘+X |
| Copy | Copy selected blocks | Ctrl+C | ⌘+C |
| Paste | Paste copied blocks | Ctrl+V | ⌘+V |
| Select all | Select all the blocks | Ctrl+A | ⌘+A |
| Fit content | Fit the content into the screen | Ctrl+1 | ⌘+1 |
Preferences¶
Language
The supported languages are:
- English
- Spanish
- Galician
- Basque
- French
- Catalan
Board rules
Enable or disable globally the board rules. These rules allow to automate tasks such as default port connections or default pin values. For example, the IceZUM Alhambra rules are:
- All not connected “clk” ports are connected to the internal CLK signal.
- All not used LEDs are turned off.
More information in the Board rules section.
Remote hostname
Set the hostame of a remote device with an FPGA board connected. The format is user@host. For example, pi@192.168.0.22. Verify, Build and Upload functions will be executed in this host, that must have apio pre-configured.
Project information¶
Contains all the information about the project:
- Name: project name
- Version: version number
- Description: information shown in the block tooltip
- Author: creator of the project
- Image: SVG shown in the block body
View¶
| Action | Description |
|---|---|
| PCF | Show the board PCF file |
| Pinout | Show the board SVG pinout |
| Datasheet | Open a web browser with the board datasheet |
| Board rules | Show the current board rules |
| Collection info | Show the current collection README file |
| FPGA resources | Show / Hide the used FPGA resources |
Select¶
Board
Select the FPGA board. The supported boards are:
- IceZUM Alhambra
- Kéfir I iCE40-HX4K
- Nandland Go board
- iCE40-HX8K Breakout Board
- iCEstick Evaluation Kit
- icoBOARD 1.0
When a board is selected all I/O block combos are updated and its current values reset.
Hint
This information is stored in the app/resources/boards directory. In order to support a new board just create a new directory with the info.json, pinout.pcf and pinout.svg (optional) files with its information. The pinout.json file must be generated from the pinout.pcf using the generator.py script.
Collection
Select the Collection from the installed collections (Tools > Collections). A collection is composed by blocks and examples. When a collections is selected, the following sections are updated with the collection content:
- File > Blocks
- File > Examples
- Menu blocks
Note
The Default collection is always available, and contains the blocks and examples distributed within the application.
Tools¶
| Action | Description | Shortcut | Mac OS |
|---|---|---|---|
| Verify | Check the generated verilog code | Ctrl+R | ⌘+R |
| Build | Synthesize the bitstream from the design | Ctrl+B | ⌘+B |
| Upload | Synthesize (if required) and upload the bitstream to the FPGA | Ctrl+U | ⌘+U |
Toolchain¶
| Action | Description |
|---|---|
| Install/Update | Install a virtualenv, apio and the required apio packages. It requires Python 2.7 |
| Remove | Remove the toolchain directories |
| Reset default | Restore the default toolchain distributed within Icestudio |
| Apio version | Show the current apio version |
Drivers¶
| Action | Description |
|---|---|
| Enable | Launch the FTDI drivers configuration. Each OS has a different process |
| Disable | Revert the FTDI drivers configuration. Each OS has a different process |
Collections¶
| Action | Description |
|---|---|
| Add | Add a ZIP file with one or more collections |
| Remove | Remove the selected collection |
| Remove all | Remove all the collections |
Note
A collection is composed by blocks and examples sorted by categories (directories). The package.json file is required and contains information about the collection. The locale directory is optional and contains the translations for the blocks and examples. A collection has the following structure:
Collection/
├── blocks/
├── examples/
├── locale/
├── LICENSE
├── package.json
└── README.md
A ZIP file of collections contains one or more Collection directories at the main level. A collection can be selected in Select > Collections.
More information in the Default collection.
Hint
When a ZIP file is added to Icestudio, it is installed in ~/.icestudio/collections.
Help¶
| Action | Description |
|---|---|
| View license | Open the Icestudio license in a web browser |
| Version | Show the Icestudio current version |
| Documentation | Open the Icestudio documentation in a web browser |
| Source code | Open the Icestudio source code in a web browser |
| Community forum | Open the FPGAwars forum in a web browser |
| About Icestudio | Information about the application |
Design¶
This is the main panel. It contains the blocks and the wires.
Pan & Zoom¶
Pan is performed using the Ctrl + mouse left button or mouse right button over the background. Zoom is performed using mouse wheel.
Select¶
Block selection is performed using the mouse left button. Blocks can be selected/unselected individually using left-click/Shift+left-click, respectively. In addition, several blocks can be selected by a selection box. When using the Shift key, the new selection is added to the previous one. A selection is canceled when the background is left-clicked.
Move blocks¶
Any block or blocks selection can be moved in the design using the mouse left button over the block or the selection. Also a blocks selection can be moved with the arrow keys.
Resize text blocks¶
Code and Information blocks can be resized with the resize tool in the bottom-right corner of the block.
Block examination¶
Non-basic blocks can be read only examined by double clicking the block using the mouse left button. This is a recursive action. In order to go back, click on the < back link or press the back key.
During the examination, pan, zoom and code navigation are enabled. Also the ‘Fit content’ action.
Note
The examination path is stored in the breadcrumbs. This allows to go back to any previous block.
Verilog error detection¶
The Verify, Build and Upload errors are captured and showed in the design with a notification.
If the error comes from a Code block it is marked in red an inline annotation is set:
If the error comes from a Constant block it is marked in red.
If the error comes from a Generic block it is marked in red.
Undo/Redo¶
Icestudio allows to undo/redo the following actions:
- Add or remove a block.
- Add or remove a wire.
- Move a block or a blocks selection.
- Edit an I/O block: name, type and value.
- Edit a Constant block: name, type and value.
- Edit a Code block: ports, parameters and content.
- Edit an Information block: type and content.
- Change the board.
- Change the language.
- Change the Project information: when undo/redo a Project information change, a clickable notification will appear to access the Project information section.
Take a snapshot¶
Taking a png snapshot of the application is as easy as press Ctrl+P. A save dialog appears to set the name and the path of the captured image.
How to...¶
Install the toolchain¶
- Install Python 2.7
- Launch the toolchain installation process
Go to Tools > Toolchain > Install. Be patient for the toolchain installation.
Note
When the toolchain is installed, the menu option changes to Tools > Toolchain > Update. Also, the toolchain can be restored to default in Tools > Toolchain > Reset default.
Update the toolchain¶
- Connect to the Internet
- Launch the toolchain updating process
Go to Tools > Toolchain > Update. Be patient for the toolchain update.
Install the drivers¶
- Install the toolchain (required for Windows)
- Enable the FTDI drivers
Go to Tools > Drivers > Enable. Each OS has a different process. This configuration requires administration privileges.
Note
In Windows, an external application (Zadig) is launched to replace the existing FTDI driver of the Interface 0 by libusbK.
In MacOS this operation requires Internet connection to allow Homebrew to install libffi and libftdi packages.
Hint
To revert the drivers configuration go to Tools > Drivers > Disable
Create a project¶
Create a new project
Go to Edit > New. A new window will be opened.
- Add blocks
There are different types of blocks:
Input/Output blocks
Click on Basic > Input or Basic > Output, write the block’s name and press OK or Enter.
These blocks can be configured as virtual (green). Then, the FPGA pin selector won’t be shown.
Also, it can be configured as buses using the
[x:y]notation (xis the most significant bit).
Constant blocks
Click on Basic > Constant, write the block’s name and press OK or Enter.
These blocks can be configures as local. Then, this parameter won’t be exported.
Code blocks
Click on Basic > Code, add the code ports. Port names are separated by a comma. E.g.:
a, b.
This block contains a text editor to write your module in verilog code. Module header and footer are not required.
Info blocks
Click on Basic > Info.
This block contains a text editor to add comments about the project.
It can be converted into a Readonly text block by editing the block (double-click).
Bit blocks
Click on Bit > 0 or Bit > 1.
These blocks are low and high logic drivers.
Logic blocks
Go to the Logic menu and select a block. This menu contains Gates, Combinational blocks and Sequential blocks.
Setup blocks
Click on Setup > Pull up or Setup > Tri-state.
The Pull up block must be connected to input ports in order to configure a pull up in the FPGA.
In this example we are going to implement an AND logic gate with its input/output pins connected to the FPGA I/O.
- Connect the blocks
Select your board
Go to Select > Board and select IceZUM Alhambra, Kéfir I iCE40-HX4K, Nandland Go board, iCE40-HX8K Breakout Board, iCEstick Evaluation Kit or icoBOARD 1.0.
Set FPGA I/O pins
Select all Input/Output blocks’ pins.
Save the project
Go to Edit > Save as and select the project name, for example myProject.
It will be saved as an .ice file.
Upload a bitstream¶
Open a project
Go to Edit > Open... and select an .ice file.
Verify the project
Go to Tools > Verify.
This option checks the generated verilog code using
apio verify.
Build the project
Go to Tools > Build.
This option generates a bitstream using
apio build.
Upload the project
Connect your FPGA board and press Tools > Upload. This option uses
apio upload.
Create a block¶
Open a project
Go to Edit > Open project and select an .ice file. It is recommended to set all the I/O ports non-FPGA ports (green) to create a block.
Verify the project
Go to Tools > Verify.
Add the project information
Go to Edit > Preferences > Project information.
Save the project
Go to Edit > Save.
Add a project as block¶
- Open or create a new project
Import the custom block
Go to Edit > Add as block... and select an .ice file.
Examine the custom block
Complex blocks can be examined by double clicking the block.
Add a collection¶
Go to Tools > Collections > Add and select a collection package (ZIP file).
Select a collection¶
Go to Select > Collections. Select a collection. The first item is the “Default” collection that is the one stored in the application.
View the selected collection info¶
Go to View > Collection info. A new window will appear with the README.md file content.
Create a collection package¶
- Create one or more collections
You can use the icm cli tool to create and update a collection.
Collection/ ├── blocks │ ├── category1 │ │ ├── block1.ice │ │ └── subcategory1 │ │ ├── block11.ice │ │ └── block12.ice │ └── category2 │ └── block2.ice ├── examples │ ├── example1.ice │ ├── example2.ice │ └── example3.ice ├── locale │ ├── en │ │ └── en.po │ ├── es_ES │ │ └── es_ES.po │ └── translation.js ├── LICENSE ├── package.json └── README.md
- ZIP all your collections
Create a ZIP file with all your created collections at the main level.
Collections.zip | ├── Collections 1 │ └── ... └── Collections 2 └── ...
Note
The file package.json must exists, and also the blocks directory and/or the examples directory. The locale directory is optional. More information in the Default collection.
Include a list file¶
If your code block contains a list file(s), for example:
$readmemh("rom.list", rom);
- Save the ice project
- Copy the list file(s) in the project directory
- Build and upload the project
Also you can include explicitly a list file in the header of a code block:
// @include rom.list
Include a verilog (header) file¶
If your code block includes a verilog (header) file(s), for example:
// @include lib.vh
// @include math.v
`include "lib.vh"
- Save the ice project
- Copy the verilog (header) file(s) in the project’s directory
- Build and upload the project
Configure a remote host¶
I you want to use a RPi, eg pi@192.168.0.22, or another computer from Icestudio as a client, first configure the host:
- Copy your SSH public key into the server
$ ssh-keygen $ ssh-copy-id -i .ssh/id_rsa.pub pi@192.168.0.22
- Install apio in the server
$ ssh pi@192.168.0.22 $ sudo pip install -U apio $ apio install --all $ apio drivers --enable # For FTDI devices
Enter the host name in Icestudio, Edit > Remote hostname
Now, Verify, Build and Upload tools will run in the selected host
Close the application¶
Go to File > Quit or click the application’s close button. If there are unsaved changes an alert will appear to confirm or cancel the action:
Project¶
Definition¶
- Version: 1.1.
- Package: project information.
- Design: board information and circuit design.
- Dependencies: all used dependencies in one level.
Extension: .ice
{
"version": "1.1",
"package": {
"name": "",
"version": "",
"description": "",
"author": "",
"image": ""
},
"design": {
"board": "",
"graph": {
"blocks": [],
"wires": []
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {}
}
Block instances¶
{
"id": "",
"type": "",
"data": {},
"position": {
"x": 0,
"y": 0
},
"size": {
"width": 0,
"height": 0
}
}
Samples¶
1. in-out¶
File: in-out.ice
{
"version": "1.1",
"package": {
"name": "in-out",
"version": "1.0",
"description": "Assign the input to both outputs",
"author": "Jesús Arroyo",
"image": ""
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "b25e5929-162c-4631-8d04-156e0b382590",
"type": "basic.input",
"data": {
"name": "in",
"pins": [
{
"index": "0",
"name": "SW1",
"value": "10"
}
],
"virtual": false
},
"position": {
"x": 224,
"y": 112
}
},
{
"id": "2a8315b1-437e-40b7-adfb-ff961a0aa8f6",
"type": "basic.output",
"data": {
"name": "out",
"pins": [
{
"index": "0",
"name": "LED0",
"value": "95"
}
],
"virtual": false
},
"position": {
"x": 488,
"y": 112
}
},
{
"id": "f8ffb071-9a46-4b46-86d2-cd5b83bae395",
"type": "basic.output",
"data": {
"name": "out",
"pins": [
{
"index": "0",
"name": "LED1",
"value": "96"
}
],
"virtual": false
},
"position": {
"x": 488,
"y": 248
}
}
],
"wires": [
{
"source": {
"block": "b25e5929-162c-4631-8d04-156e0b382590",
"port": "out"
},
"target": {
"block": "2a8315b1-437e-40b7-adfb-ff961a0aa8f6",
"port": "in"
}
},
{
"source": {
"block": "b25e5929-162c-4631-8d04-156e0b382590",
"port": "out"
},
"target": {
"block": "f8ffb071-9a46-4b46-86d2-cd5b83bae395",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {}
}
2. not¶
File: not.ice
{
"version": "1.1",
"package": {
"name": "Not",
"version": "1.0",
"description": "NOT logic gate",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20width=%2291.33%22%20height=%2245.752%22%20version=%221%22%3E%3Cpath%20d=%22M0%2020.446h27v2H0zm70.322.001h15.3v2h-15.3z%22/%3E%3Cpath%20d=%22M66.05%2026.746c-2.9%200-5.3-2.4-5.3-5.3s2.4-5.3%205.3-5.3%205.3%202.4%205.3%205.3-2.4%205.3-5.3%205.3zm0-8.6c-1.8%200-3.3%201.5-3.3%203.3%200%201.8%201.5%203.3%203.3%203.3%201.8%200%203.3-1.5%203.3-3.3%200-1.8-1.5-3.3-3.3-3.3z%22/%3E%3Cpath%20d=%22M25.962%202.563l33.624%2018.883L25.962%2040.33V2.563z%22%20fill=%22none%22%20stroke=%22#000%22%20stroke-width=%223%22/%3E%3C/svg%3E"
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"type": "basic.code",
"data": {
"code": "// NOT logic gate\n\nassign b = ~a;",
"params": [],
"ports": {
"in": [
{
"name": "a"
}
],
"out": [
{
"name": "b"
}
]
}
},
"position": {
"x": 248,
"y": 88
},
"size": {
"width": 384,
"height": 256
}
},
{
"id": "a4058fa5-b66e-4e5e-b542-28d7c3e9d3cd",
"type": "basic.input",
"data": {
"name": "",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 72,
"y": 184
}
},
{
"id": "07895985-9d14-4a6f-8f2d-b2a6ddf61852",
"type": "basic.output",
"data": {
"name": "",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 728,
"y": 184
}
}
],
"wires": [
{
"source": {
"block": "a4058fa5-b66e-4e5e-b542-28d7c3e9d3cd",
"port": "out"
},
"target": {
"block": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"port": "a"
}
},
{
"source": {
"block": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"port": "b"
},
"target": {
"block": "07895985-9d14-4a6f-8f2d-b2a6ddf61852",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {}
}
3. mux¶
File: mux.ice
{
"version": "1.1",
"package": {
"name": "Mux4:1",
"version": "1.1",
"description": "Multiplexer 4 to 1",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20viewBox=%22-252%20400.9%2081%2040%22%20width=%2281%22%20height=%2240%22%3E%3Cpath%20d=%22M-191%20419.9v-7.2l-41-11.8v40l41-11.7v-7.4zm-39%2018.5v-35l37%2010.8v13.5z%22/%3E%3C/svg%3E"
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "95f8c313-6e18-4ee3-b9cf-7266dec53c93",
"type": "basic.input",
"data": {
"name": "d",
"range": "[3:0]",
"pins": [
{
"index": "3",
"name": "",
"value": 0
},
{
"index": "2",
"name": "",
"value": 0
},
{
"index": "1",
"name": "",
"value": 0
},
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 64,
"y": 120
}
},
{
"id": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"type": "basic.code",
"data": {
"code": "// Multiplexer 4 to 1\n\nassign out = data[sel];",
"params": [],
"ports": {
"in": [
{
"name": "data",
"range": "[3:0]",
"size": 4
},
{
"name": "sel",
"range": "[1:0]",
"size": 2
}
],
"out": [
{
"name": "out"
}
]
}
},
"position": {
"x": 312,
"y": 152
},
"size": {
"width": 272,
"height": 144
}
},
{
"id": "60d40fc8-3388-4066-8f0a-af17e179a9bd",
"type": "basic.output",
"data": {
"name": "out",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 720,
"y": 192
}
},
{
"id": "f6528039-852b-41f9-aa41-268994b3f631",
"type": "basic.input",
"data": {
"name": "s",
"range": "[1:0]",
"pins": [
{
"index": "1",
"name": "",
"value": 0
},
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 64,
"y": 232
}
}
],
"wires": [
{
"source": {
"block": "95f8c313-6e18-4ee3-b9cf-7266dec53c93",
"port": "out"
},
"target": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "data"
},
"vertices": [
{
"x": 232,
"y": 176
}
],
"size": 4
},
{
"source": {
"block": "f6528039-852b-41f9-aa41-268994b3f631",
"port": "out"
},
"target": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "sel"
},
"size": 2
},
{
"source": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "out"
},
"target": {
"block": "60d40fc8-3388-4066-8f0a-af17e179a9bd",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {}
}
4. assign¶
File: assign.ice
{
"version": "1.1",
"package": {
"name": "Assign",
"version": "1.1",
"description": "Assign the value plus an offset to the 4bit output",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20width=%22557.531%22%20height=%22417.407%22%20viewBox=%220%200%20522.68539%20391.31919%22%3E%3Ctext%20style=%22line-height:125%25;text-align:center%22%20x=%22388.929%22%20y=%22571.69%22%20font-weight=%22400%22%20font-size=%22382.156%22%20font-family=%22sans-serif%22%20letter-spacing=%220%22%20word-spacing=%220%22%20text-anchor=%22middle%22%20transform=%22translate(-127.586%20-256.42)%22%3E%3Ctspan%20x=%22388.929%22%20y=%22571.69%22%3E=%3C/tspan%3E%3C/text%3E%3C/svg%3E"
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "909655b9-5ef0-4c45-9494-c0238d2e4732",
"type": "basic.constant",
"data": {
"name": "value",
"value": "4'b1110",
"local": false
},
"position": {
"x": 192,
"y": 112
}
},
{
"id": "7e351e09-634d-407c-ab7e-452519468292",
"type": "basic.constant",
"data": {
"name": "offset",
"value": "0",
"local": true
},
"position": {
"x": 328,
"y": 112
}
},
{
"id": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"type": "basic.code",
"data": {
"code": "assign out = C + D;",
"params": [
{
"name": "C"
},
{
"name": "D"
}
],
"ports": {
"in": [],
"out": [
{
"name": "out",
"range": "[3:0]",
"size": 4
}
]
}
},
"position": {
"x": 168,
"y": 232
},
"size": {
"width": 272,
"height": 80
}
},
{
"id": "ef743d41-5941-4831-becd-0d930c4eed54",
"type": "basic.output",
"data": {
"name": "out",
"range": "[3:0]",
"pins": [
{
"index": "3",
"name": "LED3",
"value": "98"
},
{
"index": "2",
"name": "LED2",
"value": "97"
},
{
"index": "1",
"name": "LED1",
"value": "96"
},
{
"index": "0",
"name": "LED0",
"value": "95"
}
],
"virtual": true
},
"position": {
"x": 616,
"y": 240
}
}
],
"wires": [
{
"source": {
"block": "909655b9-5ef0-4c45-9494-c0238d2e4732",
"port": "constant-out"
},
"target": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "C"
}
},
{
"source": {
"block": "7e351e09-634d-407c-ab7e-452519468292",
"port": "constant-out"
},
"target": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "D"
}
},
{
"source": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "out"
},
"target": {
"block": "ef743d41-5941-4831-becd-0d930c4eed54",
"port": "in"
},
"size": 4
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {}
}
5. complex¶
File: complex.ice
{
"version": "1.1",
"package": {
"name": "Complex",
"version": "1.0",
"description": "Example including projects as blocks",
"author": "Jesús Arroyo",
"image": ""
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "bfebb831-8b03-43e1-9b87-013f1b5a9cdf",
"type": "basic.constant",
"data": {
"name": "C",
"value": "4'b1010",
"local": false
},
"position": {
"x": 112,
"y": 88
}
},
{
"id": "1b3c9084-f6f1-433c-afe6-6a4e36de8c68",
"type": "777966d0c987f3eb6be83df69e69a56909f5d48d",
"position": {
"x": 112,
"y": 208
},
"size": {
"width": 96,
"height": 64
}
},
{
"id": "2716e75c-f7ad-421d-810b-63c309dd35ec",
"type": "908ca1985aff9d41059e523e10681c2fbac1ad29",
"position": {
"x": 368,
"y": 224
},
"size": {
"width": 96,
"height": 64
}
},
{
"id": "bf4b5914-c791-42d3-b876-df0e03d5a9a4",
"type": "dd6af852895fb14362cdc5cb5f47c76353d7c7ad",
"position": {
"x": 536,
"y": 224
},
"size": {
"width": 96,
"height": 64
}
},
{
"id": "0fbbb687-4a61-4b1d-a022-8884a20bef5c",
"type": "basic.output",
"data": {
"name": "led",
"pins": [
{
"index": "0",
"name": "LED7",
"value": "104"
}
],
"virtual": false
},
"position": {
"x": 704,
"y": 224
}
},
{
"id": "21e9e7f9-9b8a-4fca-904d-e266f1496454",
"type": "basic.input",
"data": {
"name": "in",
"range": "[1:0]",
"pins": [
{
"index": "1",
"name": "SW1",
"value": "10"
},
{
"index": "0",
"name": "SW2",
"value": "11"
}
],
"virtual": false
},
"position": {
"x": 112,
"y": 320
}
},
{
"id": "6c809d38-547d-4c70-92eb-2d5c389429e7",
"type": "basic.output",
"data": {
"name": "debug",
"range": "[1:0]",
"pins": [
{
"index": "1",
"name": "LED1",
"value": "96"
},
{
"index": "0",
"name": "LED0",
"value": "95"
}
],
"virtual": false
},
"position": {
"x": 704,
"y": 320
}
}
],
"wires": [
{
"source": {
"block": "21e9e7f9-9b8a-4fca-904d-e266f1496454",
"port": "out"
},
"target": {
"block": "6c809d38-547d-4c70-92eb-2d5c389429e7",
"port": "in"
},
"size": 2
},
{
"source": {
"block": "bf4b5914-c791-42d3-b876-df0e03d5a9a4",
"port": "07895985-9d14-4a6f-8f2d-b2a6ddf61852"
},
"target": {
"block": "0fbbb687-4a61-4b1d-a022-8884a20bef5c",
"port": "in"
}
},
{
"source": {
"block": "21e9e7f9-9b8a-4fca-904d-e266f1496454",
"port": "out"
},
"target": {
"block": "2716e75c-f7ad-421d-810b-63c309dd35ec",
"port": "f6528039-852b-41f9-aa41-268994b3f631"
},
"vertices": [
{
"x": 288,
"y": 288
}
],
"size": 2
},
{
"source": {
"block": "2716e75c-f7ad-421d-810b-63c309dd35ec",
"port": "60d40fc8-3388-4066-8f0a-af17e179a9bd"
},
"target": {
"block": "bf4b5914-c791-42d3-b876-df0e03d5a9a4",
"port": "a4058fa5-b66e-4e5e-b542-28d7c3e9d3cd"
}
},
{
"source": {
"block": "bfebb831-8b03-43e1-9b87-013f1b5a9cdf",
"port": "constant-out"
},
"target": {
"block": "1b3c9084-f6f1-433c-afe6-6a4e36de8c68",
"port": "909655b9-5ef0-4c45-9494-c0238d2e4732"
}
},
{
"source": {
"block": "1b3c9084-f6f1-433c-afe6-6a4e36de8c68",
"port": "ef743d41-5941-4831-becd-0d930c4eed54"
},
"target": {
"block": "2716e75c-f7ad-421d-810b-63c309dd35ec",
"port": "95f8c313-6e18-4ee3-b9cf-7266dec53c93"
},
"size": 4
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {
"777966d0c987f3eb6be83df69e69a56909f5d48d": {
"package": {
"name": "Assign",
"version": "1.1",
"description": "Assign the value plus an offset to the 4bit output",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20width=%22557.531%22%20height=%22417.407%22%20viewBox=%220%200%20522.68539%20391.31919%22%3E%3Ctext%20style=%22line-height:125%25;text-align:center%22%20x=%22388.929%22%20y=%22571.69%22%20font-weight=%22400%22%20font-size=%22382.156%22%20font-family=%22sans-serif%22%20letter-spacing=%220%22%20word-spacing=%220%22%20text-anchor=%22middle%22%20transform=%22translate(-127.586%20-256.42)%22%3E%3Ctspan%20x=%22388.929%22%20y=%22571.69%22%3E=%3C/tspan%3E%3C/text%3E%3C/svg%3E"
},
"design": {
"graph": {
"blocks": [
{
"id": "909655b9-5ef0-4c45-9494-c0238d2e4732",
"type": "basic.constant",
"data": {
"name": "value",
"value": "4'b1110",
"local": false
},
"position": {
"x": 192,
"y": 112
}
},
{
"id": "7e351e09-634d-407c-ab7e-452519468292",
"type": "basic.constant",
"data": {
"name": "offset",
"value": "0",
"local": true
},
"position": {
"x": 328,
"y": 112
}
},
{
"id": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"type": "basic.code",
"data": {
"code": "assign out = C + D;",
"params": [
{
"name": "C"
},
{
"name": "D"
}
],
"ports": {
"in": [],
"out": [
{
"name": "out",
"range": "[3:0]",
"size": 4
}
]
}
},
"position": {
"x": 168,
"y": 232
},
"size": {
"width": 272,
"height": 80
}
},
{
"id": "ef743d41-5941-4831-becd-0d930c4eed54",
"type": "basic.output",
"data": {
"name": "out",
"range": "[3:0]",
"size": 4
},
"position": {
"x": 616,
"y": 240
}
}
],
"wires": [
{
"source": {
"block": "909655b9-5ef0-4c45-9494-c0238d2e4732",
"port": "constant-out"
},
"target": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "C"
}
},
{
"source": {
"block": "7e351e09-634d-407c-ab7e-452519468292",
"port": "constant-out"
},
"target": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "D"
}
},
{
"source": {
"block": "b6bc7556-6362-45ca-80e5-6db7a3100c7d",
"port": "out"
},
"target": {
"block": "ef743d41-5941-4831-becd-0d930c4eed54",
"port": "in"
},
"size": 4
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
}
},
"908ca1985aff9d41059e523e10681c2fbac1ad29": {
"package": {
"name": "Mux4:1",
"version": "1.1",
"description": "Multiplexer 4 to 1",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20viewBox=%22-252%20400.9%2081%2040%22%20width=%2281%22%20height=%2240%22%3E%3Cpath%20d=%22M-191%20419.9v-7.2l-41-11.8v40l41-11.7v-7.4zm-39%2018.5v-35l37%2010.8v13.5z%22/%3E%3C/svg%3E"
},
"design": {
"graph": {
"blocks": [
{
"id": "95f8c313-6e18-4ee3-b9cf-7266dec53c93",
"type": "basic.input",
"data": {
"name": "d",
"range": "[3:0]",
"size": 4
},
"position": {
"x": 64,
"y": 120
}
},
{
"id": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"type": "basic.code",
"data": {
"code": "// Multiplexer 4 to 1\n\nassign out = data[sel];",
"params": [],
"ports": {
"in": [
{
"name": "data",
"range": "[3:0]",
"size": 4
},
{
"name": "sel",
"range": "[1:0]",
"size": 2
}
],
"out": [
{
"name": "out"
}
]
}
},
"position": {
"x": 312,
"y": 152
},
"size": {
"width": 272,
"height": 144
}
},
{
"id": "60d40fc8-3388-4066-8f0a-af17e179a9bd",
"type": "basic.output",
"data": {
"name": "out"
},
"position": {
"x": 720,
"y": 192
}
},
{
"id": "f6528039-852b-41f9-aa41-268994b3f631",
"type": "basic.input",
"data": {
"name": "s",
"range": "[1:0]",
"size": 2
},
"position": {
"x": 64,
"y": 232
}
}
],
"wires": [
{
"source": {
"block": "95f8c313-6e18-4ee3-b9cf-7266dec53c93",
"port": "out"
},
"target": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "data"
},
"vertices": [
{
"x": 232,
"y": 176
}
],
"size": 4
},
{
"source": {
"block": "f6528039-852b-41f9-aa41-268994b3f631",
"port": "out"
},
"target": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "sel"
},
"size": 2
},
{
"source": {
"block": "5e1563d7-86de-4618-a9b0-2a08075af9ec",
"port": "out"
},
"target": {
"block": "60d40fc8-3388-4066-8f0a-af17e179a9bd",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
}
},
"dd6af852895fb14362cdc5cb5f47c76353d7c7ad": {
"package": {
"name": "Not",
"version": "1.0",
"description": "NOT logic gate",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20width=%2291.33%22%20height=%2245.752%22%20version=%221%22%3E%3Cpath%20d=%22M0%2020.446h27v2H0zm70.322.001h15.3v2h-15.3z%22/%3E%3Cpath%20d=%22M66.05%2026.746c-2.9%200-5.3-2.4-5.3-5.3s2.4-5.3%205.3-5.3%205.3%202.4%205.3%205.3-2.4%205.3-5.3%205.3zm0-8.6c-1.8%200-3.3%201.5-3.3%203.3%200%201.8%201.5%203.3%203.3%203.3%201.8%200%203.3-1.5%203.3-3.3%200-1.8-1.5-3.3-3.3-3.3z%22/%3E%3Cpath%20d=%22M25.962%202.563l33.624%2018.883L25.962%2040.33V2.563z%22%20fill=%22none%22%20stroke=%22#000%22%20stroke-width=%223%22/%3E%3C/svg%3E"
},
"design": {
"graph": {
"blocks": [
{
"id": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"type": "basic.code",
"data": {
"code": "// NOT logic gate\nassign b = ~a;",
"params": [],
"ports": {
"in": [
{
"name": "a"
}
],
"out": [
{
"name": "b"
}
]
}
},
"position": {
"x": 248,
"y": 88
}
},
{
"id": "a4058fa5-b66e-4e5e-b542-28d7c3e9d3cd",
"type": "basic.input",
"data": {
"name": ""
},
"position": {
"x": 72,
"y": 184
}
},
{
"id": "07895985-9d14-4a6f-8f2d-b2a6ddf61852",
"type": "basic.output",
"data": {
"name": ""
},
"position": {
"x": 728,
"y": 184
}
}
],
"wires": [
{
"source": {
"block": "a4058fa5-b66e-4e5e-b542-28d7c3e9d3cd",
"port": "out"
},
"target": {
"block": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"port": "a"
}
},
{
"source": {
"block": "364b95cc-e8ff-4c65-b332-d6125c5968ee",
"port": "b"
},
"target": {
"block": "07895985-9d14-4a6f-8f2d-b2a6ddf61852",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": -38.5106,
"y": 27.9681
},
"zoom": 1.0904
}
}
}
}
}
Blocks¶
Basic blocks¶
Input block¶
- Type:
basic.input - States:
- Virtual: green
- FPGA I/O: yellow
- Show clock
Wire¶
E.g.: basic input block with value in.
{
"data": {
"name": "in",
"pins": [
{
"index": "0",
"name": "SW1",
"value": "10"
}
],
"virtual": false,
"clock": false
}
}
Bus¶
E.g.: basic input block with value in[1:0].
{
"data": {
"name": "in",
"range": "[1:0]",
"pins": [
{
"index": "1",
"name": "SW1",
"value": "10"
},
{
"index": "0",
"name": "SW2",
"value": "11"
}
],
"virtual": false,
"clock": false
}
}
Output block¶
- Type:
basic.output - States:
- Virtual: green
- FPGA I/O: yellow
- Show clock
Wire¶
E.g.: basic output block with value out.
{
"data": {
"name": "out",
"pins": [
{
"index": "0",
"name": "LED0",
"value": "95"
}
],
"virtual": false,
"clock": false
}
}
Bus¶
E.g.: basic output block with value out[1:0].
{
"data": {
"name": "out",
"range": "[1:0]",
"pins": [
{
"index": "1",
"name": "LED0",
"value": "95"
},
{
"index": "0",
"name": "LED1",
"value": "96"
}
],
"virtual": false,
"clock": false
}
}
Constant block¶
- Type:
basic.constant - States:
- Local parameter: ●
E.g.: basic constant block with value V.
{
"data": {
"name": "V",
"value": "4'b1001",
"local": true
}
}
Code block¶
- Type:
basic.code
E.g.: basic code block with input port a, output port b[3:0] and parameters C and D.
{
"data": {
"code": "reg [3:0] b_aux;\n\nalways @(a)\nbegin\n if (a == 1)\n b_aux = C;\n else\n b_aux = D;\nend\n\nassign b = b_aux;\n",
"params": [
{
"name": "C"
},
{
"name": "D"
}
],
"ports": {
"in": [
{
"name": "a"
}
],
"out": [
{
"name": "b",
"range": "[3:0]",
"size": 4
}
]
}
}
}
Information block¶
- Type:
basic.info - States: * Readonly
E.g.: basic infomation block.
{
"data": {
"info": "Lorem ipsum\n...\n",
"readonly": false
}
}
Generic blocks¶
Any project can be added as a read-only generic block:
- The input blocks become input ports.
- The output blocks become output ports.
- The constant blocks become parameters.
The block information is stored in dependencies, without the unnecessary information:
- The version number is removed.
- The FPGA board is removed.
- The FPGA data.pins are removed.
- An additional field data.size with the pins.length is created if greatter than 1.
- The data.virtual flag is removed.
E.g.: this project block.ice.
becomes this block:
{
"version": "1.1",
"package": {
"name": "Block",
"version": "1.0",
"description": "out = in ? C : D; p = q;",
"author": "Jesús Arroyo",
"image": ""
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "deddfc29-7bf1-4ac4-a24e-e91b4cc14335",
"type": "basic.constant",
"data": {
"name": "C",
"value": "4'b1111",
"local": false
},
"position": {
"x": 296,
"y": 32
}
},
{
"id": "a9f85080-6523-428b-966c-359be16be956",
"type": "basic.constant",
"data": {
"name": "D",
"value": "4'b0000",
"local": true
},
"position": {
"x": 488,
"y": 32
}
},
{
"id": "4aa2ce96-a449-42f1-b612-2c852dc50da8",
"type": "basic.input",
"data": {
"name": "p",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 680,
"y": 64
}
},
{
"id": "7f5654cf-4591-4a66-9147-d0cbdcb95f79",
"type": "basic.output",
"data": {
"name": "q",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 896,
"y": 64
}
},
{
"id": "fecaab8e-c7d4-4823-81fb-2b0d42f38026",
"type": "basic.code",
"data": {
"code": "reg [3:0] b_aux;\n\nalways @(a)\nbegin\n if (a == 1)\n b_aux = C;\n else\n b_aux = D;\nend\n\nassign b = b_aux;\n",
"params": [
{
"name": "C"
},
{
"name": "D"
}
],
"ports": {
"in": [
{
"name": "a"
}
],
"out": [
{
"name": "b",
"range": "[3:0]",
"size": 4
}
]
}
},
"position": {
"x": 248,
"y": 176
}
},
{
"id": "cbd336da-6d61-4c71-90e1-e11bbe6817fc",
"type": "basic.input",
"data": {
"name": "in",
"pins": [
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 48,
"y": 272
}
},
{
"id": "15e91005-34e6-4ce9-80b4-8c33c6c1e5a0",
"type": "basic.output",
"data": {
"name": "out",
"range": "[3:0]",
"pins": [
{
"index": "3",
"name": "",
"value": 0
},
{
"index": "2",
"name": "",
"value": 0
},
{
"index": "1",
"name": "",
"value": 0
},
{
"index": "0",
"name": "",
"value": 0
}
],
"virtual": true
},
"position": {
"x": 760,
"y": 272
}
}
],
"wires": [
{
"source": {
"block": "a9f85080-6523-428b-966c-359be16be956",
"port": "constant-out"
},
"target": {
"block": "fecaab8e-c7d4-4823-81fb-2b0d42f38026",
"port": "D"
}
},
{
"source": {
"block": "deddfc29-7bf1-4ac4-a24e-e91b4cc14335",
"port": "constant-out"
},
"target": {
"block": "fecaab8e-c7d4-4823-81fb-2b0d42f38026",
"port": "C"
}
},
{
"source": {
"block": "cbd336da-6d61-4c71-90e1-e11bbe6817fc",
"port": "out"
},
"target": {
"block": "fecaab8e-c7d4-4823-81fb-2b0d42f38026",
"port": "a"
}
},
{
"source": {
"block": "fecaab8e-c7d4-4823-81fb-2b0d42f38026",
"port": "b"
},
"target": {
"block": "15e91005-34e6-4ce9-80b4-8c33c6c1e5a0",
"port": "in"
},
"size": 4
},
{
"source": {
"block": "4aa2ce96-a449-42f1-b612-2c852dc50da8",
"port": "out"
},
"target": {
"block": "7f5654cf-4591-4a66-9147-d0cbdcb95f79",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": -1.6949,
"y": 61.9746
},
"zoom": 0.8686
}
},
"dependencies": {}
}
Board Rules¶
Icestudio board rules allow to automate tasks such as connecting all input CLK wires in a sequential circuit or initializing certain output ports to 1 or 0. The result is an easier and cleaner design. In Icestudio, rules can be enabled or disabled in “Edit > Preferences > Board rules”.
The board rules are implemented in the rules.json file in each board directory. Each rule file is attached to a specific board. For example, this could be a rules file for the IceZUM Alhambra:
File: rules.json
{
"input" : [
{
"port" : "clk",
"pin": "21"
}
],
"output": [
{
"pin": "95",
"bit": "0"
},
{
"pin": "96",
"bit": "0"
},
{
"pin": "97",
"bit": "0"
},
{
"pin": "98",
"bit": "0"
}
]
}
Input rules¶
Input rules define default connections between not connected ports with the name port and the specified FPGA I/O pin. In the example above, all not connected input ports named “clk” are automatically connected to the pin “21”.
With the rules enabled, these three designs are equivalent:
Note
If an input rule is set for ports named “clk”, it also applies to input ports with “Show clock” enabled.
Output rules¶
Output rules define default bit values for unused output FPGA I/O pins. In the example above, output pins “95”, “96”, “97” and “98” will be initialized to “0” if they do not appear in the circuit.
With the rules enabled, these two designs are equivalent:
Compilers¶
- Verilog
- PCF
- Testbench
- GTKWave
Implementation¶
Compiler source code.
Sample¶
Counter¶
{
"version": "1.1",
"package": {
"name": "counter",
"version": "1.0",
"description": "4-bit counter. N is the number of bits to count.",
"author": "Jesús Arroyo",
"image": ""
},
"design": {
"board": "icezum",
"graph": {
"blocks": [
{
"id": "02460189-14a0-48d0-ad87-74faf9a1177e",
"type": "basic.constant",
"data": {
"name": "N",
"value": "20",
"local": false
},
"position": {
"x": 376,
"y": 56
}
},
{
"id": "976c6f41-7ed1-41b5-953b-cd4a5709c701",
"type": "3e6c249e205080168c1bf4ee8dbc33b50653d5f4",
"position": {
"x": 608,
"y": 56
},
"size": {
"width": 96,
"height": 64
}
},
{
"id": "1a49c635-92d6-4641-bd3b-dbd7604a76bf",
"type": "basic.output",
"data": {
"name": "LED5",
"pins": [
{
"index": "0",
"name": "LED5",
"value": "101"
}
],
"virtual": false
},
"position": {
"x": 760,
"y": 56
}
},
{
"id": "1f3764d6-7db2-4e5a-912d-a25aad6459e2",
"type": "basic.output",
"data": {
"name": "LED4",
"pins": [
{
"index": "0",
"name": "LED4",
"value": "99"
}
],
"virtual": false
},
"position": {
"x": 760,
"y": 136
}
},
{
"id": "e38831b6-fd92-4e35-9fea-17b439002721",
"type": "basic.code",
"data": {
"code": "// Counter 4 bits\n// @include div.v\n\nwire trig; reg out;\n\nDIV #(N) div (\n .clk(clk),\n .out(trig)\n);\n\nalways @(posedge trig) begin\n if (rst == 1)\n out <= 0;\n else if (ena == 1)\n out <= out + 1;\nend\n",
"params": [
{
"name": "N"
}
],
"ports": {
"in": [
{
"name": "clk"
},
{
"name": "ena"
},
{
"name": "rst"
}
],
"out": [
{
"name": "out",
"range": "[3:0]",
"size": 4
}
]
}
},
"position": {
"x": 248,
"y": 184
},
"size": {
"width": 352,
"height": 288
}
},
{
"id": "4c30cdb0-f1af-4af1-bb4b-12e443b84a17",
"type": "basic.output",
"data": {
"name": "LEDs",
"range": "[3:0]",
"pins": [
{
"index": "3",
"name": "LED3",
"value": "98"
},
{
"index": "2",
"name": "LED2",
"value": "97"
},
{
"index": "1",
"name": "LED1",
"value": "96"
},
{
"index": "0",
"name": "LED0",
"value": "95"
}
],
"virtual": false
},
"position": {
"x": 760,
"y": 248
}
},
{
"id": "9803de82-f844-48f0-9f6a-b428395073b4",
"type": "basic.input",
"data": {
"name": "Enable",
"pins": [
{
"index": "0",
"name": "SW1",
"value": "10"
}
],
"virtual": false
},
"position": {
"x": 40,
"y": 296
}
},
{
"id": "4caf869e-5202-4aa0-acbf-14fac565eaf1",
"type": "basic.input",
"data": {
"name": "Reset",
"pins": [
{
"index": "0",
"name": "SW2",
"value": "11"
}
],
"virtual": false
},
"position": {
"x": 40,
"y": 392
}
}
],
"wires": [
{
"source": {
"block": "02460189-14a0-48d0-ad87-74faf9a1177e",
"port": "constant-out"
},
"target": {
"block": "e38831b6-fd92-4e35-9fea-17b439002721",
"port": "N"
}
},
{
"source": {
"block": "9803de82-f844-48f0-9f6a-b428395073b4",
"port": "out"
},
"target": {
"block": "e38831b6-fd92-4e35-9fea-17b439002721",
"port": "ena"
}
},
{
"source": {
"block": "4caf869e-5202-4aa0-acbf-14fac565eaf1",
"port": "out"
},
"target": {
"block": "e38831b6-fd92-4e35-9fea-17b439002721",
"port": "rst"
}
},
{
"source": {
"block": "976c6f41-7ed1-41b5-953b-cd4a5709c701",
"port": "19c8f68d-5022-487f-9ab0-f0a3cd58bead"
},
"target": {
"block": "1a49c635-92d6-4641-bd3b-dbd7604a76bf",
"port": "in"
}
},
{
"source": {
"block": "976c6f41-7ed1-41b5-953b-cd4a5709c701",
"port": "19c8f68d-5022-487f-9ab0-f0a3cd58bead"
},
"target": {
"block": "1f3764d6-7db2-4e5a-912d-a25aad6459e2",
"port": "in"
}
},
{
"source": {
"block": "e38831b6-fd92-4e35-9fea-17b439002721",
"port": "out"
},
"target": {
"block": "4c30cdb0-f1af-4af1-bb4b-12e443b84a17",
"port": "in"
},
"size": 4
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
},
"dependencies": {
"3e6c249e205080168c1bf4ee8dbc33b50653d5f4": {
"package": {
"name": "Bit 1",
"version": "1.0.0",
"description": "Assign 1 to the output wire",
"author": "Jesús Arroyo",
"image": "%3Csvg%20xmlns=%22http://www.w3.org/2000/svg%22%20width=%2247.303%22%20height=%2227.648%22%20viewBox=%220%200%2044.346456%2025.919999%22%3E%3Ctext%20style=%22line-height:125%25%22%20x=%22325.218%22%20y=%22315.455%22%20font-weight=%22400%22%20font-size=%2212.669%22%20font-family=%22sans-serif%22%20letter-spacing=%220%22%20word-spacing=%220%22%20transform=%22translate(-307.01%20-298.51)%22%3E%3Ctspan%20x=%22325.218%22%20y=%22315.455%22%20style=%22-inkscape-font-specification:'Courier%2010%20Pitch'%22%20font-family=%22Courier%2010%20Pitch%22%3E1%3C/tspan%3E%3C/text%3E%3C/svg%3E"
},
"design": {
"graph": {
"blocks": [
{
"id": "b959fb96-ac67-4aea-90b3-ed35a4c17bf5",
"type": "basic.code",
"data": {
"code": "// Bit 1\n\nassign v = 1'b1;",
"params": [],
"ports": {
"in": [],
"out": [
{
"name": "v"
}
]
}
},
"position": {
"x": 96,
"y": 96
}
},
{
"id": "19c8f68d-5022-487f-9ab0-f0a3cd58bead",
"type": "basic.output",
"data": {
"name": ""
},
"position": {
"x": 608,
"y": 192
}
}
],
"wires": [
{
"source": {
"block": "b959fb96-ac67-4aea-90b3-ed35a4c17bf5",
"port": "v"
},
"target": {
"block": "19c8f68d-5022-487f-9ab0-f0a3cd58bead",
"port": "in"
}
}
]
},
"state": {
"pan": {
"x": 0,
"y": 0
},
"zoom": 1
}
}
}
}
}
module DIV (input clk, output out);
parameter N = 22;
localparam M = $pow(2, N); // 2**N
wire clk_temp;
reg [N - 1:0] c = 0;
reg dout;
assign out = dout;
always @(posedge clk)
if (M == 0)
c <= 0;
else if (c == M - 1)
c <= 0;
else
c <= c + 1;
assign clk_temp = (c == 0) ? 1 : 0;
always @(posedge clk)
if (N == 0)
out <= 0;
else if (clk_temp == 1)
dout <= ~dout;
endmodule
Generates¶
// Code generated by Icestudio 0.3.0-beta3
// Tue, 14 Feb 2017 12:26:55 GMT
`default_nettype none
module main #(
parameter v30f40a = 20
) (
input vb8a806,
input ve0befb,
input vclk,
output v32232e,
output v1d1af8,
output [3:0] v6a65cd,
output [0:1] vinit
);
localparam p0 = v30f40a;
wire w1;
wire w2;
wire w3;
wire w4;
wire [0:3] w5;
wire w6;
assign w1 = vb8a806;
assign w2 = ve0befb;
assign v32232e = w3;
assign v1d1af8 = w4;
assign v6a65cd = w5;
assign w6 = vclk;
assign w4 = w3;
v3e6c24 vc4b1b9 (
.v608bd9(w3)
);
main_v4549a6 #(
.N(p0)
) v4549a6 (
.ena(w1),
.rst(w2),
.out(w5),
.clk(w6)
);
assign vinit = 2'b00;
endmodule
module v3e6c24 (
output v608bd9
);
wire w0;
assign v608bd9 = w0;
v3e6c24_v68c173 v68c173 (
.v(w0)
);
endmodule
module v3e6c24_v68c173 (
output v
);
// Bit 1
assign v = 1'b1;
endmodule
module main_v4549a6 #(
parameter N = 0
) (
input clk,
input ena,
input rst,
output [3:0] out
);
// Counter 4 bits
// @include div.v
wire trig; reg out;
DIV #(N) div (
.clk(clk),
.out(trig)
);
always @(posedge trig) begin
if (rst == 1)
out <= 0;
else if (ena == 1)
out <= out + 1;
end
endmodule
# Code generated by Icestudio 0.3.0-beta3
# Tue, 14 Feb 2017 12:27:00 GMT
set_io v32232e 101
set_io v1d1af8 99
set_io v6a65cd[3] 98
set_io v6a65cd[2] 97
set_io v6a65cd[1] 96
set_io v6a65cd[0] 95
set_io vb8a806 10
set_io ve0befb 11
set_io vclk 21
set_io vinit[0] 102
set_io vinit[1] 104
// Code generated by Icestudio 0.3.0-beta3
// Tue, 14 Feb 2017 12:27:03 GMT
// Testbench template
`default_nettype none
`define DUMPSTR(x) `"x.vcd`"
`timescale 10 ns / 1 ns
module main_tb;
// Simulation time: 100ns (10 * 10ns)
parameter DURATION = 10;
// TODO: edit the module parameters here
// e.g. localparam constant_value = 1;
localparam constant_N = 20;
// Input/Output
reg Enable;
reg Reset;
wire LED5;
wire LED4;
wire [3:0] LEDs;
// Module instance
main #(
.v30f40a(constant_N)
) MAIN (
.vb8a806(Enable),
.ve0befb(Reset),
.v32232e(LED5),
.v1d1af8(LED4),
.v6a65cd(LEDs)
);
initial begin
// File were to store the simulation results
$dumpfile(`DUMPSTR(`VCD_OUTPUT));
$dumpvars(0, main_tb);
// TODO: initialize the registers here
// e.g. value = 1;
// e.g. #2 value = 0;
Enable = 0;
Reset = 0;
#(DURATION) $display("End of simulation");
$finish;
end
endmodule
[*] Code generated by Icestudio 0.3.0-beta3
[*] Tue, 14 Feb 2017 12:27:07 GMT
main_tb.Enable
main_tb.Reset
main_tb.LED5
main_tb.LED4
main_tb.LEDs[3:0]