Hi, i hope you're having a great day
So i'm working on a project involving a stm32f4 and multiple other components (an ADC and a amplifier).
The stm32 is connected to the ADC via I2S and to the amplifier via I2S and also I2C.
I first soldered the stm32 to test it (i burned the chip on a previous board) and it worked perfectly fine, i was able to connect to it via stm32cube programmer and a cheap st-link v2. I also erased the memory, then i uploaded and debugged a small program (i = i + 1 in the while(true) loop), and it also worked perfectly fine. When i codes this program, i made sure that swd debugging was active.
I then reflow soldered everything, and everything went great (my different power supply are supplying the correct voltage, and everything that i could test was working well).
I did not put heat on the stm32, even if I got close with my hot air soldering tool, i never put the hot air directly on the chip. The hot air temperature was 240°C.
I had to solder some components using a soldering iron at a higher temp, and for a pretty long time (30s to 1 min), but it was far away from the stm32 (3cm) and it's a 4 layer pcb with hudge copper plane, so the heat should have dissipated before heating the stm32 too much.
I tried to use the embedded 3.3 V voltage from m'y linear regulator, but also the one from the st-link. However, as there are a lot of components using 3.3 V on my pcb, the st-link regulator was too week and couldn't provide required voltage.
I checked every line, the I2C line are pulled up to 3.3 V, and every I2S line are pulled down, except the word select going to the amplifier, which is pulled up, to 3.3 V also.
My clock (a mems oscillator) is running at 16 MHz as intended.
I connected the rst from my st-link to the nrst of the stm32 so it can reset the chip then access it using swd.
The error i get from stm32cube programmer is the following: error unable to get core ID not stm32 found!
I uploaded the schematic of the stm32 only if it help.
Thank for your help
