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MCU 8051 IDE

Last news:
2012-08-04Version 1.4.6 has been released
2012-05-17Version 1.4.5 released
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ASEM-51 MCU 8051 IDE

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2012-08-04 Version 1.4.6 has been released

Change log:

1.4.5 -> 1.4.6
* Bug fixes
* Added support for SDCC configuration on Windows
* Added support for ASEM-51 on Windows
* Added a few new shortcuts to editor

2012-05-17 Version 1.4.5 released

This version is basically the previous one (1.4.4) but with a few bug fixes included. Enjoy it! ;-)

2012-01-01 Version 1.4.3 released

What do you use the IDE for?
15 %
Education, as student
2 votes
31 %
Education, as teacher
4 votes
23 %
3 votes
15 %
2 votes
15 %
2 votes
13 votes
This new version is primarily about bug fixes, it is probably the most stable version of this IDE ever released. Happy New Year!

2011-12-03 Version 1.4.2 released

This version brings several bug fixes, a few minor improvements, and improved Windows installation process. Windows version does no longer depend on ActiveTcl. Well, there are not many new features in this version, but more importantly it is supposed to be more stable than any other version released so far. I will keep working on version 1.4.3 for which the main goal is to achieve better stability and usability of the IDE. Enjoy the new version, and please keep reporting bugs! Think of it as a Christmas present :-). Merry Christmas and happy New Year!

2011-11-16 Version 1.4.1 released

This new version should bring many new improvements and should suffer from much less bugs, or at least that's my expectation. Have a good luck with it and enjoy the new features. :) See you next year!

2010-09-11 Vesrion 1.3.8 released

After several weeks we can announce release of a new version, which primarily fixes many bugs from previous version (1.3.7) and adds a few new features and minor improvements.

And enjoy new features like:
* Configurable font size
* Breakpoints validation

Thank you for you support and don't stop reporting bugs, it really helps!

2010-04-15 Microsoft® Windows®

From now on, there is also a version for MS Windows operating system to make this software available for as many users as possible. The Windows version requires the following packages to be already installed on the system (I am sorry for that, but it's really necessary:

ActiveTcl ::
(optional) SDCC ::

The POSIX version of the IDE has always the top priority. And it is possible that some of the IDE functionality is missing due to certain limitations of MS Windows. I am not doing it intentionally, but some things are really hard to accomplish on such a limited platform like MS Windows. That's also the reason why the POSIX version has the top priority.

2010-04-07 Version 1.3.5 relesed

This new version fixes a few bugs from the previous version, there is no new functionality yet. But v1.4 is on its way.

Thanks to all who helped the project! Please continue reporting bugs and posting suggestions.

2009-09-02 Git repository

Newest versions of the IDE will be now stored in Git repository. This is the address: git://

How to download it from the Git repository:
1) Install Git

2) Run " git clone git:// "
It will create your own copy of the Git repository in the current directory.

3) Once you have an existing copy of the repository you can just update it each time when you want the fresh version.
$ git fetch origin master

a) You can try it without installation:
$ cd mcu8051ide/lib
$ tclsh main.tcl
b) You can install it:
$ cd mcu8051ide
$ ./configure && make
$ sudo su # or just "su"
$ make install
$ mcu8051ide

2009-08-23 Plan for version 1.4

The plan is:
* Add support for revision control systems (e.g. CVS, Git)
* Improve simulator (add UART and SPI simulation)
* Add support for next external assembler, concretely AS31
* Try to improve support for various HW tools
* Possibly add support for i18n (internationalization)
* And bug fixes of course ...

2009-08-21 Version 1.3 finaly released

This new version contains many bug fixes, many of them has been discovered by Miroslav Hradilek.

New features are:
* RS232/UART debugger, tool intended for debugging in real hardware applications
* Symbol list (added on the right panel)
* Assembler has now support for assigning register names to constants. So since this version you can write code like this: "
MOV ABC, #55h ; <- This will be compiled as "MOV R0, #55h"

And currently I am working on version 1.4

Have a good luck and happy coding :)

2009-08-04 Version 1.2 released

Today I have released the new version with a few new bug fixes and little improvements.

This is the first time when this IDE contain code written by someone else than me. Kostya V. Ivanov has fixed a few bugs in the simulator engine and the simulator now contain new code written by him ! Thank you Kostya V. Ivanov !

So I have invited Kostya V. Ivanov to the MCU 8051 IDE development team along with two more people, Fabricio Alcalde and Miroslav Hradílek. Lets see what will they respond ...

By the way this version doesn't contain any significant improvements, it's primarily about bug fixes

2009-06-14 Emulated UART terminal ??

Tiago Russolo, a student of electrical engineering in Brazil, would like to see an emulated UART terminal in this IDE. So after I finished a few quite important things somewhere else, I implement the emulated UART terminal. But it's hard to say when ...

2009-06-14 MCU8051IDE is going to become a part of the FEL

Well, Chitlesh Goorah said that and I have nothing more to say :)

FEL (Fedora electronic lab)

2009-06-14 Web site reconstruction

After a long time I have finally updated and upgraded this web. I hope you like it. But I must admit that I don't believe that anybody visits these sites :) ... Well, but may be I am wrong ... who knows ...

2009-06-14 The firts HW tools

This is has now its own hardware tools ! Currently there is one serial programmer and a few "education" boards. See the video , its nothing genuine, but I like blinking colorful things :) And in my opinion almost everybody like such thighs :)

2009-06-14 Version 1.1.1 released

Chnages from 1.1:
* Added utility "Special calculator"
* Added utility "Base convertor"
* Many tiny improvements
* Some bug fixes

2009-06-14 Version 1.1 released

Changes from 1.0.9:
* Added support for new MCUs from Intel®: 8031, 8751, 8032, 8752, 80C31, 87C51, 80C52, 87C52, 80C32, 80C54, 87C54, 80C58, 87C58
* Added simple hardware simulation
* Improved simulator (Implemented UART (experimental support), improved support for timers, etc.)
* Improved register watches
* Improved editor (improved autocompletion along with many other things)
* Improved panel "Instruction details"
* Improved 8-segment editor
* Bug fixes in assembler, disassembler and simulator engine
* Some other bug fixes
* Added utility "Scrible notepad"
* Improved IO ports monitor (panel "IO Ports")

2009-06-14 Version 1.0.9 released

Changes from 1.0.7:
* Added support for C language
* Added map of bit addressable area (part of the simulator)

2009-06-14 Version 1.0.7 released

Changes from 1.0.6:
* Added Stopwatch
* Improved code editor
* Some bug fixes

2009-06-14 Version 1.0.6 released

Changes from 1.0.5:
* Fixed critical bug in Assembler v1.0.5 (related to peerhole optimalizations)
* Added 8 segment LED display editor
* Added ASCII chart
* Added symbols table viewer

2008-05-20 Version 1.1 and project future

I have a good news for MCU 8051 IDE users and potencional users who are missing krucial development tools in this IDE. Currently I am working on version 1.1. I hope I will be able to release it aproximately at the end of June. Version 1.1 will have full support for C language and there will be some HW tools, USB programmer for AT89x and most propably also ICD (In-Circut Debugger) based on AT89C51RE2 (connected through USB interface) and some evaluation board. Please post me any suggestions to . By the way, original verison of MCU 8051 IDE wasn't intented for real application development, it was only an education tool. But 1.1 should change that.

2008-05-04 Version 1.0.5 released

This version has better assembler and added support for external editors and external assemblers. But it still doesn't support C language. Version 1.1 will correct this bug :). There were some issues on Kubuntu for AMD64, they should be fixed now.

Ubuntu and openSUSE user, please read this:

2008-01-14 Version 1.0 released

What OS does you use ?
33 %
Linux based
13 votes
18 %
BSD based
7 votes
10 %
Unix based
4 votes
28 %
11 votes
10 %
4 votes
39 votes
This version still haven't support for C language. Please report bugs and post your suggestions at this site. If you have some questions concerning this project feel free to discuss them here (no registraction required).

* MANY BUG FIXES ! (including critical)
* Added support for some new MCUs:
AT89S52 AT89LS51 AT89LS52 AT89S8253 AT89S2051 AT89S4051 T87C5101 T83C5101 T83C5102 TS80C32X2 TS80C52X2 TS87C52X2 AT80C32X2 AT80C52X2 AT87C52X2 AT80C54X2 AT80C58X2 AT87C54X2 AT87C58X2 TS80C54X2 TS80C58X2 TS87C54X2 TS87C58X2 TS80C31X2 AT80C31X2
* Added supprort for peerhole optimalizations
* Faster project opening
* Added interrupt monitor
* Added subprograms monitor
* Added SFR map
* Added SFR watches
* Extended command line interface
* Compiler now checks for valid memory addressing (new CLI options --iram-size --eram-size --xram-size --code-size)
* Added program hibernation capability
* Added editor commands hibernate resume switch-mcu set-xcode and set-xdata
* Added .desktop file and application icon
* Some more improvements

2007-12-20 Version 0.9.5 released

Do you want support for C language in MCU8051IDE ?
41 %
Certainly yes
14 votes
21 %
7 votes
9 %
3 votes
18 %
Certainly not
6 votes
12 %
I don't know
4 votes
34 votes
This is the firts version which is not limited to only one MCU. And there will be many more supported MCUs in the next version. Also support for C language is planned ! (see TODO section for more details). Please post any suggestions to

* Added support for AT89C2051, AT89C4051, AT89C51, AT89C51RC, AT89C52, AT89C55WD, AT89LV51, AT89LV52 and AT89LV55
* Simulator can now step back
* Added popup-based completion
* Added tooltips with detail description for bits in SFR
* Added simulator configuration dialog
* Implemented autosave
* Added Manual page
* Added support for multiview
* Some bug fixes

2007-11-21 Version 0.9.1 released

Which MCU vendor do you prefer ?
32 %
11 votes
15 %
5 votes
15 %
Silicon Labs
5 votes
24 %
8 votes
15 %
5 votes
34 votes
After a long time I have returned to development of this project and this is the first result. Next version will support more 8051 based microcontrollers.

* Removed dependency on IWidgets and Tix
* New hexadecimal editor
* New file selection dialog
* Added filesystem browser tab on left panel
* Added tips on startup
* Added editor command line
* A few bug fixes
* Some more minor improvements

2007-07-11 Version 0.9.0 released

What do you think about this project
61 %
Good, continue this way
23 votes
18 %
Poor, there is much to do
7 votes
11 %
Very poor
4 votes
11 %
Lost time
4 votes
38 votes
Differences from 0.8.7:
* Implemented graph
* Many bug fixes (GUI, compiler, memory leaks)
* Editable shortcuts
* Bookmarks for opened and project files
* Search panels in left and right panel
* Modified GUI (checkboxes, radio buttons ..)
* Support for various encodings and EOLs
* Added "Tools" -> "Change letter case", "Normalize HEX" and "SIM -> BIN"
* Added editor functions "Lowercase", "Uppercase" and "Capitalize"
* Added helpwindows for opened and project files and opened projects
* Added popup menus for entry and text widgets (globaly)
* Fixed problem with fonts (bad sizes)
* Implemented support for line wrapping (experimental)
* Added new command line options (see `mcu8051ide --help')
* More status tips and tool tips
* Added welcome dialog
* Added demonstration project
* Cleaner, faster and safer compiler
* Some more minority improvements

I hope this new version will be much more helpful than the previous one.
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