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Messages - andersm

1
General discussion / Re: Computer for Apollo
You may find this interesting: Computers in Spaceflight: The NASA Experience. It's interesting to compare the MIT-produced film's rosy tone to the criticism expressed in the book regarding their handling of the project. At the same time, it's hard to even imagine the difficulties involved in developing such critical software before the invention of most even elementary tools and practices.
3
General discussion / Re: keil 4 arm WTF
[quote author="Bertho"]Don't get me wrong, I do think that an abstraction layer (often) is a good thing. However, CMSIS is not the answer imo. The problem is that there is no general vendor consensus on which peripherals are available and how they are programmed/interact.[/quote]
CMSIS only concerns itself the processor core and the core peripherals (well, now it's called CMSIS-CORE and there's a CMSIS-DSP library, the CMSIS-RTOS specification and the debug-related bits). It was originally supposed to be a standardised driver interface, but that effort was abandoned after only managing to specify a debug-UART driver, which was then removed after one release. The peripheral libraries are completely up to the chip vendors.
4
General discussion / Re: keil 4 arm WTF
[quote author="arhi"]when I started keil I expected

NewProject -> select some of hundred dev boards out there or select a mcu -> select external osc speed -> select target mcu clock -> bang, here's a hello world project with startup code already in, with systemsetup already there setting the oscillator and a blank main() function or a main function with while(1); ...[/quote]
It's been a while since I last touched Keil, but IIRC that's pretty much what you get. One neat thing Keil has which I forgot to mention is the graphical config interface for the hardware initialization code. Configuring the clock tree, IO pins etc using drop-down menus is undeniably more convenient than writing the code yourself.
5
General discussion / Re: keil 4 arm WTF
The good things about Keil is that their compiler is excellent, the debugger is reliable (as far as embedded debuggers go), and the tracing features are pretty neat if you have the necessary hardware. It's also easy to get up and running.

On the negative sides, the IDE isn't all that great as you've noticed, and it can be restrictive compared to simple makefiles. One bizarre "feature" is that it seems the chip maker's peripheral libs bundled with the compiler are always included in your header search paths, and trying to use newer versions lead to undiagnosable compiler errors until you get everything just right. Also, last time I checked the version of GCC offered by Keil was ancient and probably not usable for anything newer than ARM7TDMI.

If the open source tools are good enough for your needs, and you don't need graphical setup wizards for everything I don't really see a reason for buying Keil or any commercial compiler for that matter.
6
General discussion / Re: Microchip USB and open source project
Since the resulting firmware image can't be GPL-compliant, you'll probably avoid a lot of trouble if you add a linking exception. To fulfil the obligations of the LGPL you may have to distribute the USB library as linkable object files, provided Microchip's license allows this.
7
Project development, ideas, and suggestions / Re: USB Password Manager
Not as exciting as rolling your own, but have you looked at Atmel's ATSHA204 chip? It contains a hardware RNG and various crypto functions, and is only about half a buck even in single quantities. One limiting factor is that when used as intended, it'll last only about 100000 power cycles as internal state is updated in EEPROM, but otherwise it looks like a very nice chip.
8
AVRDude / Re: Re: avrdude: initialization failed, rc=-2
The access rights issues should be fixable by adding a udev rule for the device. You can just make the device world-writable (which is fine for a normal desktop), or do it slightly cleaner by adding a special user group with access rights for it.
9
General discussion / Re: Turn around for SeeedStudio Fusion
My last order (placed on January 19th) took 5 days from submission to shipping, but shipping to Finland using the cheapest option took about a month. This is pretty consistent with previous orders.
11
General discussion / Re: Does aging parts cause Windows to slow down??
Any change in the electronics would be dwarfed by the impact of all random software that accumulates over the years. All those automatic update checkers and other background processes take their toll, especially on startup times.
12
General discussion / Re: ST Link and VirtualBox.
[quote author="arhi"][quote author="andersm"]
http://www.yagarto.de/
[/quote]
Dead[/quote]
Latest release is from December and has the current versions of all its components. That's over a year after the "goodbye" message was written.

Quote
[quote author="andersm"]
https://launchpad.net/gcc-arm-embedded/+download
Just a compiler without any libraries nor tools (debugger, programmer..)[/quote]
If you need libraries download them directly from ST. It's not too hard to find binaries for OpenOCD, and I bet a GDB binary is just as easy to find.

Quote
[quote author="andersm"]
https://sourceforge.net/projects/devkitpro/
never used it but from what I see it's using mingw - that's immediately turning on red lights[/quote]
Any GCC build for Windows will be using a POSIX layer. MinGW is the most native of them.

Quote
[quote author="andersm"]
http://www.mentor.com/embedded-software ... e-edition/ (can't use the hardfp abi, not otherwise limited)
closed, no debugger[/quote]
The GNU bits are open as required by the license. 90% of all the selfbuilt toolchains seem to use Mentor/CodeSourcery's source code packages.

[quote author="andersm"]
http://www.coocox.org/
[/quote]
- very limited support for mcu's (especially for stm32f4)
- uses their own libs (not that bad) but not simple to add native stm32 libraries in it[/quote]
You need a toolchain that supports Cortex-M4, not a specific chip (which CooCox definitely supports). If the chip vendor offers any support libraries of their own just download and add them. There's also no requirement that all components come in the same installer. If you're going to be switching OS just for that, keep good backups of your data files because you will be doing it a lot.
14
General discussion / Re: ST Link and VirtualBox.
Wouldn't your time be better spent getting it to work? And it's not like there's a shortage of pre-packaged GCC ARM toolchains for Windows to try.
15
General discussion / Re: Can microprocessors compile their code into ram?
ISTR reading on the ST support forums a long time ago that while their Cortex-M3s could execute code from RAM, it was at a performance penalty as SRAM bandwidth had to be shared between instruction and data fetches. However I don't think the STM32s of the time had any kind of caches, or if they did it was specifically for flash. It's however something worth checking from the device data sheets if you plan on running code from RAM.

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