He needs to explain with more detail what are those 10 devices as i said to him.

To start i think he is an student...

Perhaps he is making a master/slave thingy and he refers those 10 "devices" as 8051 slaves, or AVR slaves (as some of his previous posts). In that case i recommended him a multidrop network implemented either in RS232 or RS485 as Michael Karas said

Or maybe those 10 devices are old cammeras or anything. We should wait until he clarifies what are those 10 devices