iMX.7D JTAG_MOD default pulling

[thomaskofoedhan]

Hello Yuri,

removing my pull-up resistor on JTAG_MOD pin solved the problem, which means that the processor sees the unconnected pin as low. Measuring the pin voltage also shows a low pin signal. All this suggests to me that the datasheet table 4 on page 19 is wrong, and that at least the JTAG_MOD pin (haven't tested the other JTAG pins) has an internal on-chip pull-down resistor and NOT pull-up as stated in the datasheet.

Can you confirm this?

[franzhollerer]

> The i.MX7 Development Guide contains some misprints and now it is under consideration.

It is good to know that the documentation contains some misprints - or more precisely said: absolute incorrect and misleading information. In my humble opinion, it is embarrassing that NXP did not manage to fix the official documentation accordingly, or at least to mention the known misprints in an errata sheet.

[Yuri · Accepted solution]

Hello,

  according section 8.2.7.159 [SW_PAD_CTL_PAD_JTAG_MOD SW PAD Control Register
(IOMUXC_SW_PAD_CTL_PAD_JTAG_MOD)] of i.MX 7Dual Applications Processor Reference Manual,

(Rev. 0.1, 08/2016) - in the Control Register,  bit field PS (Pull Select) is 00 and bit PE (Pull Enable) is 1,

meaning 100K Pulling down just after reset.

  The i.MX7 Development Guide contains some misprints and now it is under consideration.

Have a great day,
Yuri

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