MODBUS Master Implementation on Micro-controller

Hi,

I am attempting to implement a MODBUS master that will run on a micro-controller. I am just a bit confused. When i send a modbus request, the client receives it processes it and sends a response back. I have a TCP connection in place. Do i have to wait for the reply or will it be immediate since TCP is full duplex?
 
A Modbus master is the 'client', which sends a message to a slave/server. The server/slave processes the master/client message and sends a response.

The time required for the slave/server to begin to send a response varies from brand/model device to device, on the order of milliseconds to seconds.

The master/client message incoming to the slave/server has to be completed in order to be processed which means that the server/slave response message is sent after the completion of the master/client poll message. So the messages are not concurrent and do not overlap in time.
 
A Modbus master is the 'client', which sends a message to a slave/server. The server/slave processes the master/client message and sends a response.

The time required for the slave/server to begin to send a response varies from brand/model device to device, on the order of milliseconds to seconds.

The master/client message incoming to the slave/server has to be completed in order to be processed which means that the server/slave response message is sent after the completion of the master/client poll message. So the messages are concurrent and do not overlap in time.
Thanks for the reply,

So from the client i send a modbus message that looks like:
[TransationID, Protocol ID, Unit ID, Function Code, Addr, Length ]

The slave receives the message processes it and sends a response back. I then have to process the message and read the data accordingly.

This this sound correct? Another question, The ip address of the modbus master is irrelevant
 
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