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lpc2292 we signal problem

Started by roelof t Hooft October 26, 2005
Hi,

I would really appreciate somebody's help with the
following :

A lpc2292 with 2 m29w320 Flash memory connected to
it. The signals :
lpc Fl
cs0 -> ce
oe -> oe
we -> we
A2-22 -> A0-20
D0-15 -> D0-15 first device
D16-31 -> D0-15 second device

idcy, wst1 and wst2 of bcfg0 are set to the max.
mw is set for 32 bits memory. Everything else is
zero.

Now I have hooked up a logic analyzer and that shows
me that the we signal is not used to write to Flash.
But instead the bls signals are active.

It would be easy to connect bls0 to the we inputs
but I would like to understand why this happens.
Does the processor "see" an one in rble no matter
what I put in it ? (philips support ?????)

roelof



An Engineer's Guide to the LPC2100 Series


> Hi,
>
> I would really appreciate somebody's help with the
> following :
>
> A lpc2292 with 2 m29w320 Flash memory connected to
> it. The signals :
> lpc Fl
> cs0 -> ce
> oe -> oe
> we -> we
> A2-22 -> A0-20
> D0-15 -> D0-15 first device
> D16-31 -> D0-15 second device
> idcy, wst1 and wst2 of bcfg0 are set to the max.
> mw is set for 32 bits memory. Everything else is
> zero.
> Now I have hooked up a logic analyzer and that shows
> me that the we signal is not used to write to Flash.
> But instead the bls signals are active.
> It would be easy to connect bls0 to the we inputs
> but I would like to understand why this happens.
> Does the processor "see" an one in rble no matter
> what I put in it ? (philips support ?????)
> roelof

Try setting the RBLE (bit 10) high in the BCFGx register. I was seeing the
exact same behavior and this got it going. From my understanding of the
description of this bit setting it low should have been correct for an 8-bit
bus???

Anyways, give it a try!

Greg Deuerling
Fermi National Accelerator Laboratory

> -----Original Message-----
> From: lpc2000@lpc2... [mailto:lpc2000@lpc2...] On Behalf
> Of roelof t Hooft
> Sent: Wednesday, October 26, 2005 6:06 AM
> To: lpc2000@lpc2...
> Subject: [lpc2000] lpc2292 we signal problem
>
> Hi,
>
> I would really appreciate somebody's help with the
> following :
>
> A lpc2292 with 2 m29w320 Flash memory connected to
> it. The signals :
> lpc Fl
> cs0 -> ce
> oe -> oe
> we -> we
> A2-22 -> A0-20
> D0-15 -> D0-15 first device
> D16-31 -> D0-15 second device
>
> idcy, wst1 and wst2 of bcfg0 are set to the max.
> mw is set for 32 bits memory. Everything else is
> zero.
>
> Now I have hooked up a logic analyzer and that shows
> me that the we signal is not used to write to Flash.
> But instead the bls signals are active.
>
> It would be easy to connect bls0 to the we inputs
> but I would like to understand why this happens.
> Does the processor "see" an one in rble no matter
> what I put in it ? (philips support ?????)
>
> roelof >
>
> Yahoo! Groups Links



I'm using the following BCFG config with one 16 bit flash (AM29DL323G):

IDCY=0
WST1=0
RBLE=1
WST2=0
MW=1

The WE line works as expected. The LPC2292 works with a core clock of
7.3728 MHz roelof t Hooft wrote:

> Hi,
>
> I would really appreciate somebody's help with the
> following :
>
> A lpc2292 with 2 m29w320 Flash memory connected to
> it. The signals :
> lpc Fl
> cs0 -> ce
> oe -> oe
> we -> we
> A2-22 -> A0-20
> D0-15 -> D0-15 first device
> D16-31 -> D0-15 second device
>
> idcy, wst1 and wst2 of bcfg0 are set to the max.
> mw is set for 32 bits memory. Everything else is
> zero.
>
> Now I have hooked up a logic analyzer and that shows
> me that the we signal is not used to write to Flash.
> But instead the bls signals are active.
>
> It would be easy to connect bls0 to the we inputs
> but I would like to understand why this happens.
> Does the processor "see" an one in rble no matter
> what I put in it ? (philips support ?????)
>
> roelof > >. >
>




--- In lpc2000@lpc2..., Greg Deuerling <egads@f...> wrote:
> Try setting the RBLE (bit 10) high in the BCFGx register. I was
> seeing the exact same behavior and this got it going.

I did and it generates the we signal when an access
is made to external Flash memory.
The text in the manual should be different :
RBLE set = WE signal enabled
RBLE cleared = WE signal disabled

The bls signals are active no matter the rble setting.
This might have something to do with the MW bits. > From my understanding of the
> description of this bit setting it low should have been correct
> for an 8-bit bus ???

Or byte wide devices on a word or double word data bus.
I think the text is confusing. > Anyways, give it a try!

I did :-)

Now I have to fix the actual writing to memory : the we signal
is present but nothing (apparantly) is written into the Flash.

Thank you.

roelof