On 27/10/11 23:17, Tom Schouten wrote:
On 10/12/2011 09:41 AM, Will Wagner wrote:
On 12/10/2011 14:25, Tom Schouten wrote:
<snip>
From my limited knowledge it seems however that it is not possible to
"fake" an interrupt, i.e.
#define CYGNUM_HAL_INTERRUPT_VIRTUAL0 33
#define CYGNUM_HAL_INTERRUPT_VIRTUAL1 34
such that these 33 and 34 vectors can be used in
cyg_drv_interrupt_create() of some eCos driver.
If I understand what you are asking for this is pretty straight
forward, in fact for the at91 there is already code doing this for the
SYS interrupt and so extending it to PIOa and PIOB is pretty easy. If
you look in packages\hal\arm\at91\var\current\src\at91_misc.c you can
see how this is done for the SYS interrupt.
Following this was indeed straight forward for a single pin.
Though this seems to break down for multiple pins, as reading the
interrupt status register
HAL_READ_UINT32(AT91_PIOA + AT91_PIO_ISR, isr);
might return multiple flags, and I don't see a way to then map this to
triggering multiple vectors.
Once the ISR is read, all the flags are reset so it's not possible to
only ack one and let it re-trigger in hardware.
Any idea how to work around that?
Extending hal_IRQ_handler() is not the way to go. Instead you should use
a trampoline ISR attached to the PIO vector. This then reads the PIO ISR
register and calls the virtual interrupts for all the active pins.
If you look in hal_arbiter.h you will find hal_call_isr() which does all
the eCos-related hard work, and an explanation of how to write your
trampoline and how to set it up.