Pad control register meaning for imx6q

[shuodo]

In the "IOMUX controller" section (pinmux) of imx6q TRM, it has many pad control registers. I don't quite understand the meaning of some of the fields in these pad control registers:

15–14 Pull Up / Down Config. Field: e.g. 00 - 100K Ohm Pull Down, 01 - 47K Ohm Pull Up.

Does it mean that this pin can have internal resister pulled up/down? If it has internal resister pulled up, is it pulled up to 1.8V or 3.3V?

7–6 SPEED field: e.g. 01 - 100 MHz, if SRE=1: 100MHz @ 1.8V, 150MHz @ 3.3V

What does this speed field mean? And what determines whether it is at 1.8V or 3.3V?

5–3 Drive Strength Field: e.g. 011 - 50 Ohm @ 3.3V, 90 Ohm @ 1.8V

Again, What does this drive strength field mean? And what determines whether it is at 1.8V or 3.3V?

[igorpadykov · Accepted solution]

Hi Shuo

for pad control usage one can look at AN5078

Influence of Pin Setting on System Function and Performance

Best regards
igor
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