Other Parts Discussed in Thread: CC1190,
I'm currently working on a custom PCB that has a STM32 MCU with a CC1120 Transceiver and CC1190 amplifier. We didn't solder the CC1190 part because we cannot successfully work the CC1120 Device. The problem is SO line never goes low and i can't start the communication. I double checked the SPI configuration and I'm pretty sure that SPI configs are okay by software. CS pin and the Reset pin of the CC1120 start with Logic HIGH by software. When I pull the CS line low my SO line never goes low. Is there any chance that this is a software problem? I will share the RF and MCU part of the schematics design.
We tested the system both with and without a Pull-Up in the MISO, MOSI, and SCK lines. Beside that there is an external 32 MHz oscillator labeled as Y2 which we do not have. As a substitute, we are using 32.768 MHz instead. Will this be a problem for the device?
And here i shared the scope results of the line and some code : STM32F446RET SPI Problem With CC1120 Device - STMicroelectronics Community
EDIT:In the current situation, we are only using Y2 with 22pF capacitors and a grounded ECXT_OSC pin. I have measured the oscillator pins and obtained the following readings:
DCPL_XOSC: 1.74V, DCPL: 1.8V, RBIAS: 1.2V.
Although these measurements seem fine to me, the problem still continues. The only thing that comes to my mind is that we are using a 32 MHz oscillator instead of a 32.768 MHz oscillator. Could this be a problem? Also, we have confirmed that the GND in the underside of the chip is well soldered.
