--- In l..., "Andrew Berney" wrote:
>
> Oddly enough we actually use an LPC2292 in one of our products so
i've just
> quickly done a test on it on the bench connecting to a FTDI chip dev
board
> we have and don't appear to be getting any dropped characters? I've
had a
> read through whats listed on your website (cheers for the write up)
but as
> of yet can't actually reproduce your results. I'm not too worried to be
> honest as our product talks to a PC based serial port at 19200 baud
so from
> your findings is never likely to run into the issue in the field,
it's just
> rather annoying that I can't seem to replicate what you found.
>
> Andy
>

Hi Andy,

Bearing in mind the sensitity of the observed anomaly to baud rate --
less than 0.3 percent variation at either way from 300 baud causes it
to go away, I am not surprised reproducing the results is not easy.

I am also keen on seeing what happens in Joel's case when the crystal
is replaced to see if it could be related to what I observed.

Drop me an email if you dont mind taking this further off-line to see
what is different between our two setups. It may tell us something.

Regards,

Jaya

An Engineer's Guide to the LPC2100 Series

Oddly enough we actually use an LPC2292 in one of our products so i've just
quickly done a test on it on the bench connecting to a FTDI chip dev board
we have and don't appear to be getting any dropped characters? I've had a
read through whats listed on your website (cheers for the write up) but as
of yet can't actually reproduce your results. I'm not too worried to be
honest as our product talks to a PC based serial port at 19200 baud so from
your findings is never likely to run into the issue in the field, it's just
rather annoying that I can't seem to replicate what you found.

Andy
-----Original Message-----
From: l... [mailto:l...]On Behalf Of
Mukund Deshmukh
Sent: 23 September 2006 14:22
To: l...
Subject: Re: [lpc2000] Re: no serial port on my PC
> Thanks to an alert by a fellow forum member, the issue has been quite
> adequately documented here:
>
> http://www.cse.unsw.edu.au/~jayas/esdk/lpc2/limitations.html
>
Dear Jaya,

This is from your web site.

//
More specifically, on LPC2292 with 14.7456 MHz crystal, both PLL and MAM
disabled, VPBDIV set to 1, UART set to 8-data 1-stop and no parity, it
works
at 230400 baud and above, but drops characters at 4800 baud and below.

The problem manifests itself only when the UART is connected to devices
(for
example FTDI chip) that can send data at full speed without any delays
between characters at specific baud rates.

//

My question are,

1. What about baud rate between 4800 -230400?

2. You also said that it works at 230400 and above

3. What happen if the serial port is PC and not FTDI chip?

Finally,

Should we conclude that problem is below 4800 AND with FTDI chip AND for
LPC2292?

Best Regards,

Mukund Deshmukh.
Beta Computronics Pvt Ltd
10/1, IT Park, Parsodi,
Nagpur-440022
Cell - 9422113746

> I trust you do not mind if I add a FAQ section with questions like
> yours and the answers to my original article ... I may do this when I
> get the time.
Thanks for the long answer. I was just trying to find out safe operating
baud rate for my LPC2XXX products.

Yes, FAQ would be great.

Best Regards,

Mukund Deshmukh.
Beta Computronics Pvt Ltd
10/1, IT Park, Parsodi,
Nagpur-440022
Cell - 9422113746

--- In l..., "Leon Heller"
wrote:
> Brendan and Jaya,
>
> Please stop this bickering, otherwise I'll put both of you on
> moderated status!
>
> Leon

Hmm.... That could be a bit too harsh. Mr Jaya is a
university lecturer and some of his students might be reading
this forum now. :)

Why not the 2 gentlemen continue their arguments in a separate
Yahoo forum? => with group title "unconfirmed bugs/shortcoming
of LPC21xxx"? invite some more neutral party like dominic rath
to moderate discussion if needed to?

And we could get rid of those CRP, Spurious Interrupt, UART...
from here once and for all?

----- Original Message -----
From: "Brendan Murphy"
To:
Sent: Sunday, September 24, 2006 10:23 AM
Subject: [lpc2000] Re: no serial port on my PC
> --- In l..., "jayasooriah"
> wrote:
>>
>> --- In l..., Mukund Deshmukh
> wrote:
>> > 3. What happen if the serial port is PC and not FTDI chip?
>>
>> Default or standard drivers for native serial port on PC can go up
> to
>> 192000 baud max. Even at this speed, if you look at the EIA data
>> stream you may be able to catch extraneous gaps at frequent
> intervals
>> that is attributed to driver delays.
>>
>> When and where this happens depends on the PC hardware, BIOS
> firmware,
>> operating system, and what was loaded and/or running in memory at
> the
>> time of the experiment.
>>
>> I have had reports it does show up with native PC ports, but
> nothing
>> significant enough for me to set aside time to look into it.
>> A simple "no, I haven't seen the problem without the FTDI" would
> have sufficed in answering this, the most important, question.

Brendan and Jaya,

Please stop this bickering, otherwise I'll put both of you on moderated
status!

Leon

--- In l..., "rtstofer" wrote:

> Heck, this is nothing! Wait until some unsuspecting newbie asks about
> CRP!

Now that you asked about CRP, let me tell you how it all started ...

Nah ... just kidding!

Jaya

--- In l..., "jayasooriah"
wrote:
>
> --- In l..., Mukund Deshmukh
wrote:
> > 3. What happen if the serial port is PC and not FTDI chip?
>
> Default or standard drivers for native serial port on PC can go up
to
> 192000 baud max. Even at this speed, if you look at the EIA data
> stream you may be able to catch extraneous gaps at frequent
intervals
> that is attributed to driver delays.
>
> When and where this happens depends on the PC hardware, BIOS
firmware,
> operating system, and what was loaded and/or running in memory at
the
> time of the experiment.
>
> I have had reports it does show up with native PC ports, but
nothing
> significant enough for me to set aside time to look into it.
>

A simple "no, I haven't seen the problem without the FTDI" would
have sufficed in answering this, the most important, question.

Brendan

--- In l..., wagner@... wrote:
> Hey! Could you stop this in public?

Heck, this is nothing! Wait until some unsuspecting newbie asks about
CRP!

You just have to sit back and relax, smoke 'em if you have 'em.

Richard

Hey! Could you stop this in public? When people subscribe here they expect
learn and share about LPC2000, not read about unresolved love stories. Go
private, please.

Citando jayasooriah :

> --- In l..., "John Heenan" wrote:
> >
> > This is with regard to the claim of Jaya that the LPC UART is faulty.
> >
> > Jaya is a university staff member in New South Wales Australia who
> > gets paid from public tax payers money.
>
> I wish :) As a matter of fact I do not get paid by the UNSW. One the
> other hand I pay more tax than I wish I had to!
>
> > As such he has an automatic
> > standing and so we should expect certain standards.
>
> Yes and I believe I do live up to this expectation.
>
> > Also Jaya
> > deliberately conducts himself in a style that attempts to portray an
> > image that he is a credible expert.
>
> I do not do this deliberately. Please accept this as my personal
> apology to you John Heenan if I did and this offended you. It is
> probably because I am frequently called in as an independent expert on
> various matters relating to computer systems.
>
> HOWEVER, my dear John Heenan, this thread is NOT about the life and
> career of Jayasooriah.
>
> Stop stooping low this extent each time you want to use this forum as
> a soap box to post long stories. You use this ONE excuse to make
> THREE posts. Sheesh!
>
> > However Jaya has not helped
> > Brendan reconcile differences in results and Jaya has failed to
> > provide complete information.
>
> I cannot not see one good reason why I should. On the other hand I
> can think of many why I should not.
>
> I am sorry I appear not do not take every remark someone makes in this
> forum seriously and respond with intricate details. I have work to do.
>
> > Please note I am not making a claim that Jaya's results are not true.
>
> Thank you very much. This is a good note on which I like to get off
> this (your) thread.
>
> Kind regards,
>
> Jaya
>
>

--- In l..., "John Heenan" wrote:
>
> This is with regard to the claim of Jaya that the LPC UART is faulty.
>
> Jaya is a university staff member in New South Wales Australia who
> gets paid from public tax payers money.

I wish :) As a matter of fact I do not get paid by the UNSW. One the
other hand I pay more tax than I wish I had to!

> As such he has an automatic
> standing and so we should expect certain standards.

Yes and I believe I do live up to this expectation.

> Also Jaya
> deliberately conducts himself in a style that attempts to portray an
> image that he is a credible expert.

I do not do this deliberately. Please accept this as my personal
apology to you John Heenan if I did and this offended you. It is
probably because I am frequently called in as an independent expert on
various matters relating to computer systems.

HOWEVER, my dear John Heenan, this thread is NOT about the life and
career of Jayasooriah.

Stop stooping low this extent each time you want to use this forum as
a soap box to post long stories. You use this ONE excuse to make
THREE posts. Sheesh!

> However Jaya has not helped
> Brendan reconcile differences in results and Jaya has failed to
> provide complete information.

I cannot not see one good reason why I should. On the other hand I
can think of many why I should not.

I am sorry I appear not do not take every remark someone makes in this
forum seriously and respond with intricate details. I have work to do.

> Please note I am not making a claim that Jaya's results are not true.

Thank you very much. This is a good note on which I like to get off
this (your) thread.

Kind regards,

Jaya