Open Source Renesas

We would like your opinion regarding open source!

Why do people like open source? What would you, as a programmer, be looking for in Open Source regarding Renesas?

If an Open Source group focusing on Renesas products was to be started what would you like to see done?

Would anyone be interested in joining?

I like open source because if a program doesn't quite do what you need, you can change it, adapt it to your situation.  You can't do that with closed source.  Worst case with open source, you can pay someone else to make the changes you need, but at least you have the option.

As for Renesas, yes, I'm interested in anything that applies open source to at least the r8c/m16c/m32c families, but then again I'm biased - I wrote the gcc port for them, and the simulator gdb uses for them, and maintain the m32c ports of those and other tools on behalf of the FSF.  My furnace has five R8C chips managed by a Linux SBC, all programmed with open source tools.

The most important thing a focus group here can do is gather up all the hardware and software specs and techniques that are needed to apply open source solutions to development needs, such as programming interfaces (for example, does *anyone* know how to parallel-program an m32c chip?) and early access to chip specs.

I'd like to see more open-source hardware designs in addition to open source code.

There's a project called the RepRap that is intriguing that may be able to teach us some things about hardware design.

http://en.wikipedia.org/wiki/RepRap_Project

Note that the project is being done with a very capable CAD package called KICAD. KICAD runs in Linux, Windows and MAC OS. It offers schematic capture, SPICE simulation support, PCB layout/design, and 3D simulations of boards. And it is free. The best part is that they've got libraries ported from Eagle that include many Renesas chips.

http://en.wikipedia.org/wiki/Kicad

Let's share code and designs.

I agree that Open Source can drastically improve system functionallity and reduce development time, both for commerical as well as hobby/student/whatever projects. I use the M16C/62 MCU on an embedded system equipped with a Bluetooth module. We rely heavily on the lwIP IP stack. Without it we would be years from the point where we are now in terms of functionallity. However, one lacking part of the Renesas development platform is an open source compiler. We started to look at gcc for m16c, but the limitation of only 16-bit pointers allows only 64k to be directly addressed, which when using TCP/IP and Bluetooth is not enough. The M16C MCU gives our sensor node the perfect match between low power consumption and memory (flash and RAM), but without support for a free C/C++ compiler which can use the full address range, we belive that it will be limited to people and organisations that can afford to buy commercial compilers, such as the IAR Embedded workbench.

Does your chip have more than 64k of ram?  I mean, do you need gcc to access more ram, or do you just need the constant data moved to flash to make more room in ram for dynamic data?  There are patches in the works to let gcc put constants in flash, freeing up some of the ram, but they won't be in 4.3.

For the m32c chips, pointers are 24 bits, although individual data items are limited to 16 bits because the m32c chips are missing a lot of 24 bit math operations.

(yes, I'm the m32c maintainer for gcc)

Would be nice to have constant data in flash. Then we don't need to rewrite a lot of existing code. We can manage to get some functionality but to be fully flexible the patches you mention will be of great value Before we stored our web pages in constant data, but when we skipped them, the IP stack seems to be working fine. We are using a M16C/62P with 31kB of RAM. Now we copy .rodata to RAM at boot, which works fine, even though we "waste" precious RAM by that approach... Great job with the port btw!

Open source is fantastic way to foster interest and publicity in hardware and software with minimal effort compared to conventional marketing. It has a snowball effect and can quickly gain momentum without the 1st party (Renesas in this case) dumping tons of money into it.  Gigantic open source success stories include Linux,  http://sourceforge.net/ , http://slashdot.org/ , etc. In a more broad category, the simple success of online communities - Wikipedia, YouTube, and online forums - requires rethinking old promotional strategies. Hobbyists and professionals have a lot in common when it comes to learning new microcontroller platforms and can enrich each other's experiences through open source and other means. Personally, I know I would be a lot further along with my M16C project if the M16C had fraction of the open source/free/hobbyist code available for it as other competing platforms. It's a technically strong product but it lacks the same vocal fan base as certain competitors.

Various companies (eg. Renesas) offer design contests where they hand out prizes for user submitted code and projects. This creates good reference material for the products. However, the companies have to set up and pay for the the contests. You can compare this model with the more organic 'free for all' approach where you can see dozens of hobbyist/professional projects around the internet for a given chip. The company doesn't own the code these people produce, but the immense popularity and strong community is  quite reassuring when trying out a new platform.

Unfortunately I really haven't answered your question about what Renesas should do specifically with an open source group. But I think the general idea is superb, and I look forward helping and benefiting from the to the projects that can emerge from it. So long as the developers understand the spirit and practice of open source software, it's hard to go wrong with starting it up!

RenesasRulz makes it really easy to create a Web Page for your own projects, so they can be viewed and understood by a wide audience of users.

We've recently added a new "object" that can be created to hold uploaded projects: the Rich Document.

Users can Add a Rich Document to their member folder, and attach HTML formatted text, along with pictures, and ZIP files, etc.  It's just like publishing to your own website, but easier and more "public."

Don't forget to "submit" the content you create - so it can be shared.