Lpc2000

Hi all,

has anybody tried to put the LPC in power down mode?
What would be the proper sequence of putting it into power down mode
and wake on external interrupt?
I have done the following:

(will use EINT2 for wakeup, the program starts with EINT2 mapped to IRQ)

............

power down:

- disable EINT2 interrupt
- EXTWAKE = 4
- PCON = 2
(here the processor stops)

but on triggering EINT2 the processor does not continue running,
have to reset the controller instead (undesirable).

Any ideas/hints? 

Thank you

Nedeljko

--- In lpc2000@yahoogroups.com, "nedeljkomiljevic"
<nedeljkomiljevic@y...> wrote:
> Hi all,
> 
> has anybody tried to put the LPC in power down mode?
> What would be the proper sequence of putting it into power down mode
> and wake on external interrupt?
> I have done the following:
> 
> (will use EINT2 for wakeup, the program starts with EINT2 mapped to
IRQ)
> 
> ............
> 
> power down:
> 
> - disable EINT2 interrupt
> - EXTWAKE = 4
> - PCON = 2
> (here the processor stops)
> 
> but on triggering EINT2 the processor does not continue running,
> have to reset the controller instead (undesirable).
> 
> Any ideas/hints? 
> 
> Thank you
> 
> Nedeljko

Hi,

I'm doing the same thing and I'm still trying to figure out how to
wake the unit up. I think 
you maybe missing something. My sequence in powering down is this:

set EINT0 to port 16 (PINSEL1) (I'm using EINT0)
EXTWAKE = 1
PCONP = 0 (all peripherals off)
PCON = 2

I already tried generating a low on EINT0 to wake up and nothing's
happening. I'd be glad 
to know your progress. :)

jpsg123

Hi,

well, the unit does something on exiting the poer down mode but I
have a feeling that the peripherals (e.g. UARTs) could be in need of
re-initializing...I could see some (strange) activity on the UART0.
Your power down sequence basically does not differ from mine (apart
from powering off all peripherals). Will keep posting on progress :-)


Nedeljko


--- In lpc2000@yahoogroups.com, "jpsg123" <jpsg123@y...> wrote:

> 
> Hi,
> 
> I'm doing the same thing and I'm still trying to figure out how to
> wake the unit up. I think 
> you maybe missing something. My sequence in powering down is this:
> 
> set EINT0 to port 16 (PINSEL1) (I'm using EINT0)
> EXTWAKE = 1
> PCONP = 0 (all peripherals off)
> PCON = 2
> 
> I already tried generating a low on EINT0 to wake up and nothing's
> happening. I'd be glad 
> to know your progress. :)
> 
> jpsg123

Well, good to hear you at least are seeing the cpu wake up. My problem is I can't make it 
wake up at all. :(

jpsg123

--- In lpc2000@yahoogroups.com, "nedeljkomiljevic" <nedeljkomiljevic@y...> wrote:

> 
> Hi,
> 
> well, the unit does something on exiting the poer down mode but I
> have a feeling that the peripherals (e.g. UARTs) could be in need of
> re-initializing...I could see some (strange) activity on the UART0.
> Your power down sequence basically does not differ from mine (apart
> from powering off all peripherals). Will keep posting on progress :-)
> 
> 
> Nedeljko
> 
> 
> --- In lpc2000@yahoogroups.com, "jpsg123" <jpsg123@y...> wrote:
> 
> 
> > 
> > Hi,
> > 
> > I'm doing the same thing and I'm still trying to figure out how to
> > wake the unit up. I think 
> > you maybe missing something. My sequence in powering down is this:
> > 
> > set EINT0 to port 16 (PINSEL1) (I'm using EINT0)
> > EXTWAKE = 1
> > PCONP = 0 (all peripherals off)
> > PCON = 2
> > 
> > I already tried generating a low on EINT0 to wake up and nothing's
> > happening. I'd be glad 
> > to know your progress. :)
> > 
> > jpsg123

I finally got the thing to work. I was writing to the wrong address space for the external 
interrupt registers. On exit from power down, I do need to enable PLL again (because I'm 
running at 60Mhz) and since I did not enable the external interrupt, it took quite a while to 
figure out that I still need to clear the int flag or else the cpu won't go to sleep the next 
time. Anyways, FYI.

jpsg123

--- In lpc2000@yahoogroups.com, "jpsg123" <jpsg123@y...> wrote:

> Well, good to hear you at least are seeing the cpu wake up. My problem is I can't make it 
> wake up at all. :(
> 
> jpsg123
> 
> --- In lpc2000@yahoogroups.com, "nedeljkomiljevic" <nedeljkomiljevic@y...> wrote:
> > 
> > Hi,
> > 
> > well, the unit does something on exiting the poer down mode but I
> > have a feeling that the peripherals (e.g. UARTs) could be in need of
> > re-initializing...I could see some (strange) activity on the UART0.
> > Your power down sequence basically does not differ from mine (apart
> > from powering off all peripherals). Will keep posting on progress :-)
> > 
> > 
> > Nedeljko
> > 
> > 
> > --- In lpc2000@yahoogroups.com, "jpsg123" <jpsg123@y...> wrote:
> > 
> > 
> > > 
> > > Hi,
> > > 
> > > I'm doing the same thing and I'm still trying to figure out how to
> > > wake the unit up. I think 
> > > you maybe missing something. My sequence in powering down is this:
> > > 
> > > set EINT0 to port 16 (PINSEL1) (I'm using EINT0)
> > > EXTWAKE = 1
> > > PCONP = 0 (all peripherals off)
> > > PCON = 2
> > > 
> > > I already tried generating a low on EINT0 to wake up and nothing's
> > > happening. I'd be glad 
> > > to know your progress. :)
> > > 
> > > jpsg123