Lpc2000

alan_in_nz wrote:

>I am using an LPC2148 with a 32.768KHz crystal on the RTC oscillator 
>pins. I need to internally route the resulting 32.768KHz clock and 
>output it to a GPIO pin. Is this possible? If so how and what pin is 
>best to use as the output GPIO pin? The datasheet I have been looking 
>at does not seem to have (as far as I can see) a detailed block 
>diagram which shows the clock schemes for this device and how I could 
>achieve this. If anyone has done this or knows how to do this I would 
>appreciate the help. Thanks. Alan
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That sounds odd.  I had to put a resistor in series with the crystal to 
drop the drive level of the LPC2xxx oscilator circuit.  That circuit 
should have plenty of output level to drive other logic?  If not, why 
not just stick a FET into the osc circuit and buffer your 32KHz into 
your other logic?

TomW


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-- 
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
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