Multiple slaves to single master - Wiring connections

Hi Team,

Hope you all are keeping safe!

I am comparatively new to modbus communication and have recently started testing on it. I know how the serial and TCP communication works incase of 1 master 1 slave configuration.

But how should my wiring look like if I want to connect 4 slaves to one master in case of serial communication if i want to conenct these in daisy chain form? I have three wired cable and port. Rx, Tx and ground. Also is it necessary that all the four slaves should use either RS232 or RS485 only in this configuration.

Additionally and this is different question just for my information, is it possible that two slaves use TCP and two will use serial communication? I think we will need some adapter?

Thank you so much in advance for your help!
 
RS-232 is point-to-point ONLY, so it can only be used for single master, single slave. Multiple slaves need to run on a multidrop RS-485 bus. A master with an RS-232 port would need an RS-232/485 converter for a multi-drop RS-485 network.

RS-485 bus wiring is 'daisy chain' wiring: Rx to Rx to Rx, Tx to Tx to Tx, gnd to gnd to gnd.

Termination resistor is installed across the Tx and Rx driver lines at the ends of the bus only, never in the middle of the bus.

There are commercial 'serial server' converters that convert RS-485 to Ethernet. Be sure to get one that is specifically for Modbus because of Modbus RTU's timing requirements, the generic 485/Ethernet boxes usually do not work reliably.. The converter boxes require some configuration with a utility program.
 
RS-232 is point-to-point ONLY, so it can only be used for single master, single slave. Multiple slaves need to run a multidrop RS-485 bus. A master with an RS-232 port would need an RS-232/485 converter for a multi-drop RS-485 network.

RS-485 bus wiring is 'daisy chain' wiring: Rx to Rx to Rx, Tx to Tx to Tx, gnd to gnd to gnd.

Termination resistor is installed across the Tx and Rx driver lines at the ends of the bus only, never in the middle of the bus.

There are commercial 'serial server' converters that convert RS-485 to Ethernet. Be sure to get one that is specifically for Modbus because of Modbus RTU's timing requirements, the generic 485/Ethernet boxes usually do not work reliably.. The converter boxes require some configuration with a utility program.
Perfect!! Thanks alot!!
 
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