2023-10-08 02:48 AM
Hello Community!,
I am working on STM32F745IG, where i am interfacing 24 SPI slaves to STM32F745IG MCU. Please let me know how many slaves can be connected to single SPI interface in STM32F745IG?. I looked into datasheet, I couldn't able to find.
Thank you.
2023-10-08 06:34 AM
With that many slaves I'd suggest that you really should mux/buffer every signal. Capacitive loading alone will wreck the edge rates. For any significant clock rate and/or trace distance I'd be very, very careful of signal integrity beyond about 4 or 5 slaves per F7 SPI.
2023-10-08 03:42 PM
This is limited by the board layout, not the STM32. If you are using slowish speeds (say 1 MHz or under) and have short traces from MCU to slave, 24 slaves should work be just fine.
2023-10-08 03:48 PM
Buffers and line decoders, could likely do it with much lower pin-count device.