hai to all

what are spi extenders? what is the use of it?

is spi communication is bi-directional? if yes when i connect multiple slaves with master if individual slave will communicate with the master? if so when more than one slave will communicate at the sametime to the same master what happens?
or
all the slave SDO are tied together and fed to the SDI and slaves are controled through individual slave select line?

kindly clarify my doubts?

 

It's normally a master to slave relationship. If you want multi master then I2C might be a better choice.