MrBool
Posts: 103
Joined: Sat Jul 05, 2014 9:51 am

Two LAN9514, one crystal oscillator

Wed May 29, 2019 1:33 pm

I would like to use two LAN9514 with CM3. Is possible to clock them both with one crystal oscillator? For the first one I will use crystal oscillator, not signal from CM3.
I noticed that LAN9514 has 24MHz reference clock output but it is not useful for the second LAN9514 because it needs 25 MHz.

fruitoftheloom
Posts: 20129
Joined: Tue Mar 25, 2014 12:40 pm
Location: Delightful Dorset

Re: Two LAN9514, one crystal oscillator

Wed May 29, 2019 1:49 pm

MrBool wrote:
Wed May 29, 2019 1:33 pm
I would like to use two LAN9514 with CM3. Is possible to clock them both with one crystal oscillator? For the first one I will use crystal oscillator, not signal from CM3.
I noticed that LAN9514 has 24MHz reference clock output but it is not useful for the second LAN9514 because it needs 25 MHz.

Recently another developer had a similar requirement:

viewtopic.php?f=98&t=239594
adieu

Asus CS10 Chromebit / HP Envy 4500 Wireless Printer / Raspberry Pi Model 2B v1.1 / RealVNC Software...

hippy
Posts: 5578
Joined: Fri Sep 09, 2011 10:34 pm
Location: UK

Re: Two LAN9514, one crystal oscillator

Wed May 29, 2019 4:27 pm

MrBool wrote:
Wed May 29, 2019 1:33 pm
I would like to use two LAN9514 with CM3. Is possible to clock them both with one crystal oscillator?
It may be possible to take XO from the one with the crystal and feed that to the XI of the one without. That may require a buffer. Otherwise use an oscillator module and feed its output to both XI.

Return to “Compute Module”