LPCXpresso IDEのトピックRe: Getting the clock signal

Getting the clock signal

lpcware — Wed, 15 Jun 2016 23:03:41 GMT

Content originally posted in LPCWare by shobley on Wed Sep 22 11:39:25 MST 2010
I'm currently experimenting with the LPCXpresso board, but since they did not have a support forum, I thought I would post my question here.

Does anyone know if I can access the 12Mhz clock signal and use it to drive another device (Pixart sensor)?

Or is there a way to generate an 8-12Mhz clock signal from one of the pins without too much load.

Ideally I would just like to tap the built in crystal, but using some kind of PWM has been known to work with the Atmel AVR chips.

Any help greatly appreciated.

Steve

Re: Getting the clock signal

lpcware — Wed, 15 Jun 2016 23:03:42 GMT

Content originally posted in LPCWare by renan on Wed Sep 22 11:44:14 MST 2010
This is the LPCXpresso forum. :D

Renan

Re: Getting the clock signal

lpcware — Wed, 15 Jun 2016 23:03:42 GMT

Content originally posted in LPCWare by Jesse.Rosenberg on Wed Sep 22 12:35:01 MST 2010
The clock output pin is primarily intended for diagnostic purposes, rather than for clock synthesis. Using a divider value of 2, for instance, can be used to observe an internal 100MHz clock frequency using lower end lab equipment, such as a USB based oscilloscope with limited bandwidth.

You should bear in mind that should your design make use of in system programming (ISP) via the chip's boot loader for software updates, you'll most likely be using P0_1, which is typically a clock output pin.