If I remove the SMT32L476RGT6U IC from the Nucleo board first. Then Is it possible to connect SMT32L476RGT6U IC in an external board with STLink pins (CN4) of the Nucleo-L476 (IC is removed) board?

[Prajnyajit]

1. If I remove the  SMT32L476RGT6U IC on the Nucleo L476 board.
2. I will mount the  SMT32L476RGT6U IC on an external PCB.
3. Now, I will connect the required pins of IC with CN4 of the Nucleo Board.

Is it possible for debugging for external application? My intension is to use STM Nucleo board CN4 to debug instead of one extra STLINK V2 or V3. Is it possible ?

Pin connections will be as follows.

[Prajnyajit]

Now modified. Is it ok?

I have already referred manuals and trying to finalize them. Could you please say is it ok or not? NRST will be connected to the ST-LINK Reset pin when debugging and after the program is loaded it can be connected to VDD with a 10K resistor. Is it ok now?

[TDK]

> NRST should be connected to VDD via cca 10k rezistor. No capacitor needed.

NRST has an internal pullup and does not require an external one.

The bypass cap is recommended by ST to avoid spurious resets, which can happen. It recommended in the datasheet, which you suggest looking at, but provide contradicting advice.

[Prajnyajit]

Done and schematic is made. I need a proper verification. Can you help me in this?

[Prajnyajit]

Oh, then I was right I think. Thank you TDK for your valuable support. I have modified it, please check.

NOTE: what I understood is, NRST will be connected to the ST-LINK MCURST pin when debugging and after the program is loaded and it is ready to run, it can be connected to GND.

Is it ok now?

Rest all ok?

[Peter BENSCH]

NRST: does not necessarily need a pull-up resistor because a pull-up is already included.

BOOT0: it may be better not to switch the 10k with the switch between GND and VDD, but to connect the 10k resistor directly to GND and, if necessary, to connect BOOT0 to VDD with a NO switch.

HSE: Rext at the 8MHz crystal might not be necessary, please read AN2867, e.g. section 3.5.3. It is also particularly helpful to work through section 3, because the crystal connection is often neglected - it is definiely not enough to simply connect an 8MHz crystal. Section 7 is also very important, especially pictures 11...13, which deal in detail with the correct layout.

Regards

/Peter

[Prajnyajit]

I have modified it. But regarding HSE, should I remove this 8MHz crystal oscillator and go?

[Prajnyajit]

I have referred to the datasheet which is attached. I have connected the 8MHz referring to the datasheet only.

[MM..1]

Last my reply... Your question If i removethe STM IC ... No you dont need remove MCUs from Nucleo boards, but you need handle Nucleo schematics part Default - Reserved jumpers FYI

 Simply in CN2 is on normal Nucleo mode two jumpers and when you remove you can connect external board to CN4...

[Prajnyajit]

Peter ! Can you please tell me your valuable opinion?

[Prajnyajit]

ok