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Can not connect to target

Ozzys
Associate II

0690X00000BvnAcQAJ.png0690X00000BvnAXQAZ.png0690X00000BvnA3QAJ.jpg0690X00000Bvn9yQAB.jpg0690X00000Bvn9tQAB.jpg0690X00000Bvn9oQAB.jpg

10 REPLIES 10
Ozzys
Associate II

Hi guys, this is my first question on this community, I really did a lot of work on this pcb, I tried to make a custom made PCB board with the STM32F030RCT, So I tried to program the microcontroller with ST-LINKv2 programmer via SWD& SWDIO. I download the needed driver for the st-linkv2 but I still can not program the microcontroller, the output = 'Can not connect to target' using stm32CUBEIDE really tried everything to program it. I even tried the usb to uart cp2104 to program but even that did not work. All VCC are correct 3.3 Volts and there is no shortcircuit. I measured all VCC and the RST pin and boot0 pin and the capacitors are correct.

Make sure the part orientation is correct, Don't confuse ejector pin marks for pin 1 mark.

The external ST-LINK/V2 pod needs power on Pin 1 or 2 for the buffer logic.

The secondary signs-of-life method is to have BOOT0 High, and send an 0x7F data pattern at 9600 8E1 (Even Parity) and observe a 0x79 response.

Use RealTerm in Hex mode, and look at AN2606 for pins used by the boot loader.

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Ozzys
Associate II

The first signs-of-life methode1 : Pin 1 is marked here, is this right? The datasheet was bit confusing but this seems right to me? This seems to be right, I connected the 3.3V and GND as shown in the picture, also the SWDIO and SWCLK and reset pin.

The secondary signs-of-life methode2: Yes I did switches the BOOT0 pin to 3.3 Volts (see schematic label ResetUART). I measured the boot0 pin and its perfectly high if I place the jumper , if I remove the jumper it goes to zero volts for the SWDIO and SWD programming mode like in methode 1. So after downloading software and opening flash loader demonstrator , the responder does not connect on any bautrate or any parity mode, so I cant even connect it from the flash loader demonstrator. 0690X00000BvoCeQAJ.jpg0690X00000BvoCKQAZ.png

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Ozzys
Associate II

I bought an ECS-320-12-36-CKM-TR crystal oscilator , and provided it with 2x 2pF capacitors. I was thinking Maybe the osscilation is not working?

Piranha
Chief II

That part is just a crystal without oscillator circuit and 2 pF is almost definitely not enough for it. From popular values 18 pF could be the most appropriate one, or probably 15 pF. Read this:

https://blog.adafruit.com/2012/01/24/choosing-the-right-crystal-and-caps-for-your-design/

But the MCU starts with internal oscillator anyway, therefore it shouldn't matter at this point. Probably try 10k pull-down resistor for BOOT0 and disconnect 47k pull-up resistor from NRST like in AN4325 figure 9. Have you read that document? 🙂

Ok, so chip doesn't seem to be functioning. Pin 1 looks to be correctly orientated.

Still most probably pins and/or power

The crystal isn't important for the ST-LINK or USART methods.

Check the state of the NRST pin, if it is always low, check the VDDA

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Ozzys
Associate II

@Piranha A type fault of me , I mean I put two 12 pF capacitors, and yes that right it has to start with the internal oscillator anyway. Yes I have put an 100k resistor from BOOT0 to GND and disconnected 47k pull-up resistor from NRST but it still does not work, i even have a switch to reset the uC my self but even this does not work. VDDA=3.3V like it should be and NRST pin is 3.3 V high. NRST does not go low when I try to program it, with the oscilloscope on the NRST pin, the scope showed me the status with trigger mode, I can tell clearly that the reset pin does not go low when I send the program the the microcontroller, only if I reset the pin my self with the switch.

Ozzys
Associate II

@Community member​ VDDA status as shown on figure.

0690X00000BvqzJQAR.jpg

Piranha
Chief II

> Yes I have put an 100k resistor from BOOT0 to GND

I said 10k and that's what ST recommends.

> NRST does not go low when I try to program it

I thought you have connected it to the debugger's RST pin!?