Using Serial Peripheral Interface (SPI) to talk to several slaves simultaneously

问题

I have four Atmega328p in a single board and I want one of them send the same data (i.e. sensor readings) to the other three simultaneously. I'm not interested in a bidirectional communication. I read this thread (How can I broadcast data to multiple SPI slaves and how it works?) about SPI broadcasting, and someone mentioned not being possible because in SPI communication is full duplex and MISO and MOSI lines are active at the same time. However, I was wondering if I could just let the MISO lines unconnected and all SS pins pulled low, so I could broadcast a message to all slaves simultaneosly, taking into account that I do not need any type of response from the slaves to the master.

So, is this possible? Or how else could I work around this problem? I was also considering on using UART's Tx line and connect all the receivers in parallel to it, but I'm not sure that would work too.

Thanks for your attention.

来源：https://stackoverflow.com/questions/50312318/using-serial-peripheral-interface-spi-to-talk-to-several-slaves-simultaneously