STM32h753x - JTAG interface

[DJ_IND]

We are planning to use STM32H753X in one of our design. For JTAG interface I can see two options 5 pin and 4 pin JTAG. Is STM32H753 supports 4 pin JTAG? If yes, how to manage NJTRST pin? Shall i connected NJTRST pin to NJRST?  what is the use of 5 pin JTAG over 4 pin JTAG?

[KDJEM.1 · Accepted solution]

Hello @DJ_IND;

The core of STM32H74xI/G and STM32H75xI/G devices integrates the Serial Wire/JTAG Debug Port (SWJ-DP). It is an ARM® standard CoreSight™ debug port that combines a 5-pin JTAG-DP interface and a 2-pin SW-DP interface.
• The JTAG Debug Port (JTAG-DP) provides a 5-pin standard JTAG interface to the AHP-AP port.
• The Serial Wire Debug Port (SW-DP) provides a 2-pin (clock + data) interface to the AHP-AP port

I recommend you to look at AN4938 Application note Getting started with STM32H74xI/G and STM32H75xI/G
MCU hardware development for JTAG connection.

I hope this help you.

Thank you.

Kaouthar