Yahoo Groups archive

Lpc2000

Index last updated: 2026-04-28 23:31 UTC

Thread

Minimalist dynamic params on DS.

Minimalist dynamic params on DS.

2004-06-16 by nonuckingfumber

Maybe I am missing something, but the datasheet for the 210x (5th Feb
2004) seems to have minimalistic parametrs. The max input frequency at
fosc input is specified for ext source, crystal and with the PLL. The
highest value is ext. source @ 50MHz

Section on the PLL notes that the max PLL multiplier will be 6 on this
chip.

The bulleted features at the start of the data sheet states that Max
clok speed is 60MHz.

The DS notes that one of the reasons for having a divider for access
to the VFB is that this is not capable of running at full CPU speed.

Put it all together then I assume (if using a parameter from the
'features' list is OK) that the max CPU frequency is 60MHz but of
course I must use  the PLL to get this (probably 4 x from a 14,7MHz
quartz). It does not say how long I should allow for the PLL to stabalize.

Nor does it say how fast the VFB can run at. It says it resets to /4
to ensure the VFB runs at boot. Given that the max input is 50MHz and
no PLL is present at reset, one can only assume that it cannot support
25MHz, or it would be possible to reset the bus to /2.

Checked out the app notes on the Phillips site and there is no
additional info there either.

I hate to be pedantic but I am trying to minimise baud rate error on
obsure high speed rates, and this very much depends on the VFB clock.

Re: Minimalist dynamic params on DS.

2004-06-16 by nonuckingfumber

I have now found the Phillips FAQ. Apparently (and in contrast with
what is stated on the DS) I **can** run the VFB at full speed. It also
explains how to start up the PLL (which I have also found in source
code examples).

Perhaps I should throw away the datasheet and just use support
material ;-)

Re: Minimalist dynamic params on DS.

2004-06-16 by lpc2100_fan

Another source of information is the User's Manual. This usually 
describes how to program peripherals while the data sheet only 
includes a (very brief) description.
Don't know why Philips does not find a better way to promote the 
User's Manual, it is a pain in the b... to find.
FYI, it can be downloaded here:
http://www.semiconductors.philips.com/acrobat/usermanuals/UM_LPC2106_2
105_2104_1.pdf


Beware if you have a slow connection, 2.4 MB

Cheers, Bob


--- In lpc2000@yahoogroups.com, "nonuckingfumber" 
<nonuckingfumber@y...> wrote:
> I have now found the Phillips FAQ. Apparently (and in contrast with
> what is stated on the DS) I **can** run the VFB at full speed. It 
also
Show quoted textHide quoted text
> explains how to start up the PLL (which I have also found in source
> code examples).
> 
> Perhaps I should throw away the datasheet and just use support
> material ;-)

Re: Minimalist dynamic params on DS.

2004-06-16 by lpc2100_fan

The link in the previous e-mail might be brokwn because of the wrap 
around caused by the stupid advertisement.

Use this one:
www.philipsmcu.com/acrobat/usermanuals/UM_LPC2106_2105_2104_1.pdf

Bob

--- In lpc2000@yahoogroups.com, "lpc2100_fan" <lpc2100_fan@y...> 
wrote:
> Another source of information is the User's Manual. This usually 
> describes how to program peripherals while the data sheet only 
> includes a (very brief) description.
> Don't know why Philips does not find a better way to promote the 
> User's Manual, it is a pain in the b... to find.
> FYI, it can be downloaded here:
> 
http://www.semiconductors.philips.com/acrobat/usermanuals/UM_LPC2106_2
> 105_2104_1.pdf
> 
> 
> Beware if you have a slow connection, 2.4 MB
> 
> Cheers, Bob
> 
> 
> --- In lpc2000@yahoogroups.com, "nonuckingfumber" 
> <nonuckingfumber@y...> wrote:
> > I have now found the Phillips FAQ. Apparently (and in contrast 
with
> > what is stated on the DS) I **can** run the VFB at full speed. It 
> also
> > explains how to start up the PLL (which I have also found in 
source
Show quoted textHide quoted text
> > code examples).
> > 
> > Perhaps I should throw away the datasheet and just use support
> > material ;-)

Re: [lpc2000] Re: Minimalist dynamic params on DS.

2004-06-17 by Robert Adsett

At 11:10 PM 6/16/04 +0000, you wrote:
>Don't know why Philips does not find a better way to promote the
>User's Manual, it is a pain in the b... to find.

It's right on the main product page under support and tools.  Just how 
would they make it much more obvious?

http://www.semiconductors.philips.com/pip/LPC2104.html

Robert


" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

Re: [lpc2000] Re: Minimalist dynamic params on DS.

2004-06-17 by Alaric B Snell

Robert Adsett wrote:
> At 11:10 PM 6/16/04 +0000, you wrote:
> 
>>Don't know why Philips does not find a better way to promote the
>>User's Manual, it is a pain in the b... to find.
> 
> 
> It's right on the main product page under support and tools.  Just how 
> would they make it much more obvious?
> 
> http://www.semiconductors.philips.com/pip/LPC2104.html

Likewise, it is linked to from the Wiki I set up for this kind of thing:

http://www.open-research.org.uk/ARMuC/

...along with all the other links to manufacturer's pages I could find. 
And it's a Wiki, so people can contribute their own links, experiences, 
hints and tips!

> 
> Robert
> 

ABS

Re: Minimalist dynamic params on DS.

2004-06-17 by hodgejackiehank

Users manual describes the family, it does not, and should not, define
the timing parameters. These should be on the datasheet for the
individual device version, and in the section on dynamic
parameter....not the features list.

The procedure for locking onto the PLL should be in the users manual,
and not in the FAQ.

On the whole, Phillips documentation is not bad, but not the best. I
would give it a 7/10.....sufficient!

IMHO, the american manufacturers (Motorola, Intel, Microchip ecc.) Get
the best balance with datasheets and appnotes. The Oriental
manufacturers (Toshiba, Sharp etc.) manage to put down tons of figures
but I can never quite manage to work out what I want to know. European
manufacturers (Phillips, ST etc) are hanging in the balance....I
understand what they do say but many things seem to be missing or
misplaced!

I think the core ARM documention is very good....but perhaps there is
some personal bias here, I am English ;-)



--- In lpc2000@yahoogroups.com, Alaric B Snell <alaric@a...> wrote:
> Robert Adsett wrote:
> > At 11:10 PM 6/16/04 +0000, you wrote:
> > 
> >>Don't know why Philips does not find a better way to promote the
> >>User's Manual, it is a pain in the b... to find.
> > 
> > 
> > It's right on the main product page under support and tools.  Just
how 
Show quoted textHide quoted text
> > would they make it much more obvious?
> > 
> > http://www.semiconductors.philips.com/pip/LPC2104.html
> 
> Likewise, it is linked to from the Wiki I set up for this kind of thing:
> 
> http://www.open-research.org.uk/ARMuC/
> 
> ...along with all the other links to manufacturer's pages I could find. 
> And it's a Wiki, so people can contribute their own links, experiences, 
> hints and tips!
> 
> > 
> > Robert
> > 
> 
> ABS

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.