On the iMX8 Nano, where is the JTAG_TRST pin (also mentioned in the Reference Manual as the JTAG_TRSTB pin)?
For example, in the Reference Manual I can find things like this:
And things like this:
It appears I can find references to the JTAG_TRST pin, but I cannot seem to find the pin itself.
Here's what I have found:
- The SPF-31407 baseboard schematic reference design seems to show options for zero-ohm resistors to connect the nRST signal of the JTAG header to either the processor POR_B signal, or to the processor BOOT_MODE2 signal.
- For the iMX8 Nano, using the BOOT_MODE2 signal doesn't make sense to me (yet), however the POR_B signal might. Figure 4-24 in the Reference Manual shows the POR and TRST signals being AND'd together, which might imply that either signal could be used.
Given the above, am I correct in saying:
- There is no JTAG_TRST pin on the iMX8 Nano
- Use the POR_B pin as a substitute for the JTAG_TRST pin (connected using a series diode as per the SPF-31407 schematic)