Lpc2000

----- Original Message ----- 
From: "Alaric B Snell" <alaric@...>
To: <lpc2100@yahoogroups.com>
Sent: Wednesday, February 04, 2004 1:56 PM
Subject: [lpc2100] Real time clock


> 
> Looking at the LPC210x manual, the real time clock:
> 
> 1) Needs to be set up for the crystal frequency / PLL settings
> 
> 2) Will not tick during Power Down mode
> 
> This means that the contents of the clock are a bit fragile, really - 
> suggesting it will be better used as a local 'cache' of an external 
> seperately-clocked real time clock unit that's slow to access (I2C or 
> similar), loaded from it during startup or return from power down mode 
> after setting up the PLL and the RTC divider registers. Unless you have 
> a setup that's rarely reset and never put into power down mode, it's not 
> all that useful, as I see it.
> 
> Anyone else had any thoughts about it? It would have been nice if they 
> provided an external 32,768Hz clock input pin to run the RTC off of when 
> the MHz oscillator was down!
> 
> On the other hand, it occurs to me that the PLL seems amply capable of 
> producing processor clock frequencies far in advance of the rated 60MHz 
> - overclocking! How soon before we see huge copper heatsinks with fans 
> for LPC2100s, eh? ;-)

Someone posted their experiences with overclocking a few weeks ago.

Leon
--
Leon Heller, G1HSM
Email: aqzf13@...
My low-cost Philips LPC210x ARM development system:
http://www.geocities.com/leon_heller/lpc2104.html