Does ST20 CPU supports modbus TCP/IP ??

Josh Elliott

Hi,

Taking the following example you can setup a simple MODBUS master-slave communication between s7-200 SMART and Sinamics v20.

Note:Find the Sample Program in the attachment.

Requirement:
To operate the MODBUS protocol you must first procure and install first the STEP7Micro/WINSMART

Parameter matching
For MODBUS communication, on the master side you need library blocks "MBUS_CTRL" and "MBUS_MSG"

MBUS_MSG

Parameter	Meaning	Selection options
EN	Release
First	Activation
Slave	Slave address
RW	"Read" or "Write"	0=read, 1=write
Addr	MOBDUS initial address	0 .. 128 = digital outputs Q0.0 .. Q15.7 10001 .. 10128 = digital inputs I0.0 .. Q15.7 30001 .. 30092 = analog inputs AIW0 .. AIW62 40001 .. 49999 = holding register2
Count	Number of bits (0xxxx, 1xxxx) / words (3xxxx, 4xxxx)
DataPtr	Pointer to start of variable memory
Done	'Finished' message
Error	Error code	1)

MASTER

MBUS_CTRL

Parameter	Meaning	Selection options
EN	Release
Mode	Protocol specification	0=PPI, 1=MODBUS
Baud	Transmission rate in kbps	1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200
Parity	Parity	0=none, 1=odd, 2=even
Timeout	Maximum time in ms for the slave's response
Done	'Finished' message
Error	Error code	1)

 ST20 CPU can support modbus TCP/IP ??

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Split from S7-200 SMART with V20(Modbus).