Enable only SWD from fusemap and ignore pin JTAG_MOD

[mperez1]

Hello there,

We have a custom board with i.MXRT1052. In this design we are using the pin JTAG_MOD as an input for an interrupt, in order to being able to debug in SWD mode we added a pull_down. But now the problem is that when we connect the interrupt line we obtain a high level on that pin and the SWD debug is disable for the JTAG mode.

So the question is, there is any way in the fusemaps to disable the JTAG mode regardless that we have the JTAG_MOD pin in high state? 

I have read the "AN12419 Secure JTAG for i.MXRT10xx" and the Figure 1 suggest me that this is not possible. Anyone can give any other insight? 

Thank you in advance,

Miguel

[victorjimenez · Accepted solution]

Hello Miguel, 

There isn't any fuse in the fusemap that you can burn to disable the JTAG interface but keep the SWD functionality. You need to connect the JTAG_MOD pin to GND and remap your external interrupt to a different pin, there's no other option. 

Regards, 

Victor