I don't know what kind of LD3320 module you are using,
There are two common types of LD3320 modules.
One is the SPI interface of the module itself, and SPI communication control is carried out by connecting the single chip computer.
The other is that the module itself has been integrated with a single chip microcomputer chip, and the module data will provide the operation routines and instructions.
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From what you've described, it's probably the first scenario.
Provide SPI to operate this module of the function STM32, according to the Arduino code adjust accordingly on the line.