must USB1 use PLL1 for clock?

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must USB1 use PLL1 for clock?

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by petekol on Wed Apr 27 08:31:14 MST 2016
i see and wonder following in User Manual (LPC43xx UM10503) for USB1:


Quote:

BASE_USB1_CLK:

Uses PLL1. CLK_USB1 must
be 60 MHz when the USB1 is
operated in low-speed and
full-speed modes. In
high-speed mode, the clock
is provided by the ULPI PHY



Must i use PLL1 direct? or can it be over clock divider A-E (it is still not to get 60Mhz if running 204Mhz)?
or i can use PLL0 running 480Mhz , divide it by 8 and set it to BASE_USB1_CLK? - my preferred option

Table 121 shows that i can't use divider>4 for PLL0USB... can i use PLL0AUDIO?

thank you
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lpcware
NXP Employee
NXP Employee
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by petekol on Tue May 03 00:42:44 MST 2016
i answer to my q myself, good forum support -))

"Uses PLL1" is wrong and misleading in UM. Any clock source can be used.

What was really hard to find is that USB_EPWR bit in SFSUSB reg should go high - no mention of this in USB1 chapter....-(((
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