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- Feb 15, 2014
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Full disclosure: This whole C2000 LPC saga has me increasingly confused the deeper I look into it.
If any of these fixes are to work, what we need is to supply a high rail to be pulled down by the CPU when it wants to output logic low (or it wants to detect the boot mode on power-up) - that's not 3.3V, it'll depend on the IC, but Intel specifies 2 V for the LPC bus. So, as long as logic high is consistently decently above 2 V, all's good.
That said, I'm not following the benefit of the divider versus a straight pull-up.
If any of these fixes are to work, what we need is to supply a high rail to be pulled down by the CPU when it wants to output logic low (or it wants to detect the boot mode on power-up) - that's not 3.3V, it'll depend on the IC, but Intel specifies 2 V for the LPC bus. So, as long as logic high is consistently decently above 2 V, all's good.
That said, I'm not following the benefit of the divider versus a straight pull-up.