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As the subject states, I am interested in changing the 24 MHz crystal on my PSoC5LP development board to and 18.5 MHz crystal. Will this cause me any problems or can I just swap it and go?
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Programmable Clocks
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USB needs 48 Mhz on PSOC, why 24 Mhz is used X 2.
If you need another frequency consider PSOC 4 which has fractional
clock dividers, or using verilog to generate a fractional divider to gen
the 18.5 Mhz. Note the downside is clock jitter in these techniques.
As well as absolute accuracy due to finite resolution of the technique.
http://www.cypress.com/?id=2401 Discussion half way down the page
Google "verilog fractional clock dividers", you will get a lot of hits.
Regards, Dana.
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Afaik the crystal is used to precisely generate the clock for the USB-component(s). When you do not need USB capabilities there's nothing against changing the quartz.
Bob
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USB needs 48 Mhz on PSOC, why 24 Mhz is used X 2.
If you need another frequency consider PSOC 4 which has fractional
clock dividers, or using verilog to generate a fractional divider to gen
the 18.5 Mhz. Note the downside is clock jitter in these techniques.
As well as absolute accuracy due to finite resolution of the technique.
http://www.cypress.com/?id=2401 Discussion half way down the page
Google "verilog fractional clock dividers", you will get a lot of hits.
Regards, Dana.
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