Hi Vinod,

Here is a cheapest mehtod that can solve your problem. You will need to write a software on PC side that implements a proper protocol so that 10 devices can communicate in the following manner.



When a device needs to send data to PC.

1. It will just send data as it was sending to a directly connected PC.
2. The 8051 microcontroller shown will recieve the data through bit banged UART and keep it in its internal ram temporarily.
3. The 8051 will send start conversation signal sequence to PC.
4. The 8051 will send PC the device address that needs to communicate.
5. 8051 will then start sending the data message to PC.
6. When done 8051 will send stop conversation signal sequence.

When PC needs to send data to a device

1. PC will send start converstion signal to 8051.
2. PC will send the device address that it wants to communicate with.
3. PC will send the data message to 8051.
4. The 8051 will then send the data to the appropriate device through bir banged UART.

If you want you can also implement a CRC16 or something that will ascertain correct data sending and reception.

Regards,
Prahlad Purohit



Regards,
Prahlad Purohit