Understand how to integrate MCU on custom PCB and program it.

[JCorl.1]

Hello. I have been messing around with the STMF407VG for a few weeks now using a discovery board. Been the steep learning curve but I think I have made significant progress on learning firmware development on it. I have gotten my code to be to a point where I wanted to have a custom PCB solution. I went ahead and looked at a few implementations of other STM32 dev boards and used that to help understand how to connect everything up.

I finally got my boards in the mail. Power seems to be okay to the target, I measured the power rails for all of the pins and looks okay. Both boot pins are grounded, and the reset line is held high. Though when I try to upload a blank project to my custom PCB, I get the error that there is "No device found on target". Only thing I can think of is that I must have miswired the port that connects to the ST LINK V2 I purchased. I never made a custom PCB with an ARM MCU before so this is my first go at it. I have attached a picture of the MCU section of the schematic. Is there perhaps some green horn mistake I made?

Any hints are welcome!

[Tesla DeLorean]

Nothing jumping out immediately

Check orientation

Check voltages on VCAP pins, expecting around 1.25V

[JCorl.1]

I measure 1.263V for both Vcaps. I did need to make an adapter board. On my PCB, I have a 50mil spacing 20 pin connector, I made a breakout board to convert from 50mil to 100mil. It doubles the length from the programmer.

[JCorl.1]

The target PCB.

[MM..1]

In your schematics i dont see SWD interface for connect ST LINK V2. Seems you have JTAG exposed then in sw you need change connection method from SWD to JTAG.

But for next design i recommend use SWD interface.

[Tesla DeLorean]

Surely it would work either way, SWD is a subset of the JTAG pins.

You'd want an authentic ST-LINK/V2 where pin 1/2 at the lower 2.5V power the target side buffers in the debug pod.

[JCorl.1]

Well I feel silly, my adapter board was not making good connection. I jammed the connector in some more and now it connects successfully. Thank you both for being so quick to help though. This is why I keep using ST products, the forum is extremely helpful!