Re: [libopenstm32-devel] gpio_toggle and examples question

[Uwe H. <uw...@he...>]

Hi,

On Fri, Jan 28, 2011 at 03:10:35AM -0600, Marko Kraljevic wrote:
> Hi, I just got a little STM32 discovery board, came across a post from 
> Uwe somewhere mentioning libopenstm32 and the script to build the 
> toolchain. I got it up and running and have been playing around a little 
> bit.

Nice! I also have one of those around now. How do you program them
though? AFAIK it needs SWD and last time I check OpenOCD support for SWD
was not ready yet. Do you use some tool which relies on the internal
bootloader?


> I modified examples/button.c to work with the discovery board (should I 
> be submitting examples modified for this target, anyway? Could be handy, 
> as the board is 10 bucks.. nice way to get into ARM, I thought).

Sure, having a few examples for the STM32 discovery board would be nice.

 
> Anyway, I started to play with a few of the library routines, and 
> gpio_toggle doesn't exactly work with multiple GPIOs. If you have some 

Yep, known limitation.


> void gpio_toggle(u32 gpioport, u16 gpios)
> {
> 	GPIO_ODR(gpioport) = GPIO_IDR(gpioport) ^ gpios;
> }

This one is probably the best option.


> I suppose it's the same deal either way, just not sure what is 
> preferred. I've made a little wig-wag blinker to demo it, if there is 
> any want for it.

Sure.

 
> What else...
> Regarding the clock setup bits, eg. 
> rcc_clock_setup_in_hse_8mhz_out_72mhz() - Is there any thought of moving 
> this to a more universal function? say like:
> rcc_clock_setup_hse(in_mhz, out_mhz) - or so? Do you think this is 
> worthwhile?

Hm, good question. Not sure if it's worth the trouble, but it wouldn't
hurt either, I guess.


> (the MCU on this board only goes to 24MHz, so I've just 
> added a in_hse_8MHz_out_24MHz function temporarily).

 
> Is there a delay function in the works?

Nobody I know of is working on it, but it's definately something we need!
(timer-based, exact delay instead of the current "loop" quick hack)


> What areas of the lib need help?

Various, an incomplete and outdated (and way too unspecific) status page
is at:

http://sourceforge.net/apps/mediawiki/libopenstm32/index.php?title=Status

Having specific, working examples for each subsystem would be great, for
example. One or two header files may be missing, too. Proof-reading the
headers for typos is also a good thing to do, it's easy to miss some
typos when you add new #define lists.

Other than that, currently some work is going into timers, CAN
(I think), USB, and I'll personally probably make an FSMC example sooner
or later, as I want to design a hardware with some STM32 that can
read/write NAND flash.

 
Uwe.
-- 
http://hermann-uwe.de     | http://sigrok.org
http://randomprojects.org | http://unmaintained-free-software.org