[En-Nut-Discussion] Why not change from Nut/OS to BeRTOS

[Harald Kipp]

Hi all,

I have no idea how to proceed... I'm in a very bad mood... :-(

I failed to get an old application working, which I know for sure had
been working previously. Obviously the SPI chip selects for the VSCODEC
are not properly initialized.

Diving into the code, I found

GpioPinConfigSet(VSCODEC0_XCS_PORT, VSCODEC0_XCS_BIT, GPIO_CFG_OUTPUT);

which translates via the Configurator into

GpioPinConfigSet(AVRPORTD, 6, GPIO_CFG_OUTPUT);

In include/dev/gpio_avr.h we have

#define PIOD_ID     4
#define AVRPORTD    PIOD_ID

so the call again translates to

GpioPinConfigSet(4, 6, GPIO_CFG_OUTPUT);

and in gpio_avr.c we have

int GpioPinConfigSet(int bank, int bit, uint32_t flags)
{
...
 if (flags & GPIO_CFG_OUTPUT) {
  AVR_DDRX(bank) |= _BV(bit);
 }
}

which translates, according to gpio_avr.h

#define AVR_DDRX(bank)  (_SFR_IO8(bank -1))

This is finally _SFR_IO8(3), but should have been _SFR_IO8(0x11).

How the hell can it be, that AVR GPIO code, which had been working all
the time, seems to be completely broken for many months (r4642 - 24th
Sept. 2012). Note, that setting wrong I/O registers may cause hardware
damage.

The crowning glory is found at line 66 of nut/arch/avr/dev/gpio_avr.c.

Gosh! We exchanged a lot of email filled with high level discussions
about GPIO tricks, optimizations, compiler issues etc. etc. etc. And now
it turns out, that not even the basics are working.

As this module is used in several hardware-independent Nut/OS drivers
I'd consider Nut/OS severely broken for the AVR platform since months.
This is ridiculous and unacceptable. If I were a harmless user only, I'd
see Nut/OS very badly maintained and give BeRTOS, Femto OS or whatever a
try. Unfortunately I'm part of the developer team.

We definitely have to implement some kind of quality procedures ASAP.

Regards,

Harald

P.S.: Well, after cooling down a bit, I'm considering, that I may have
overlooked something. In that case, please send your flames to my
private email address.