2021-05-05 10:41 AM
Hi,
I have designed a custom board based on a F417, I am trying to program it with an ST-Link V2 through SWD(SWCLK, SWDIO, GND and RST) and I only get: Error: No STM32 target found!
I have tried the CubeProgrammer, the STLink Utility, the CubeIDE, with modes Normal, Under Reset, Power Dowm... and nothing works.
The PCB traces are connected directly from the SWD header to the pins, but I have also tried with some PullUp-Down resistor on the lines, as a few designs have, and nothing...
I attach a screencapture of the PCB design file, 4 layers, used top and bottom for signals, 2nd for GND and 3rd for 3.3V, 100nF for each VDD pin...
I have tested all the sldering, and it is correct too.
I don't know what can I do from now.
Thank you so much
Best regards
2021-05-05 10:58 AM
Likely an implementation detail rather than the tools. Indicating the part is currently in a non-functioning state.
Review Schematic
Check Orientation
Check supplies, especially VDDA / VSSA
Check VCAP pins and capacitors 2.2uF, 1.25V ?
Check voltage level observed on NRST
2021-05-05 11:25 AM
Hi,
I think that orientation is correct, point mark of the chip at the pin 1 corner.
VDDA is filtered by a FB and a 100nF from 3.3V, VSSA to GND.
VCAP 2.2uF for each VCAP pin, and 3.3V measuded when powered.
NRST behaves well, pulled high, filtered near the chip with 100nF.
Thank you
2021-05-05 12:11 PM
An authenticate/external ST-LINK/V2 expects pin 1 or 2 of the 20-pin header to be provided with the Target's supply voltage, VTarget = VCC 3.3V
The tools should report the voltage observed.
2021-05-05 01:15 PM
Yes, the softwares report 3.21V, I think that the problem is on V_CAPs, I have wired them to VCC bypassed with 2.2uF, but they don't go to 3.3V.
I will try to modify it, and will keep you updated.
Thank you so much!
2021-05-06 07:00 AM
> I think that the problem is on V_CAPs, I have wired them to VCC bypassed with 2.2uF, but they don't go to 3.3V.
V_CAP should not be tied to VCC. They are nominally ~1.2V.