In fact the Cortex STM32F103 has 2 SPI, and they are in use.
Nevertheless, as you propose a multiplexed solution could resolve this, the SPI Slave select signal could give 4 slaves addresses.
In fact the Cortex STM32F103 has 2 SPI, and they are in use.
Nevertheless, as you propose a multiplexed solution could resolve this, the SPI Slave select signal could give 4 slaves addresses.