ElmoMC Multi-Axis Motion Controller-Maestro - Manual (Page 223)

12.2 Serial RS-232 media
NOTE:
Before using the Maestro serial port for MODBUS purposes, you MUST disconnect it
from the command interpreter by sending the
rsauto(0) command from the terminal
and switching power supply to OFF/ON.
12.2.1 Communication parameters for ASCII or RTU
• MODBUS address (view paragraph 12.1.1)
• Serial port
Serial port identifier
Default port value "COM1"
• Baud rate
Port baud rate in bps (typically 1200-115200 ,maximum Value depends on UART
hardware)
Default value - 38400
• Data bits
Port data bits: (for RTU Must be SER_DATABITS_8)
Default value - 8
• Stop bits
Port stop bits: (typically value 1 - 2)
Default value - 1
• Parity
Port parity: no parity, odd parity or even parity
Default value - no parity
12.3 MODBUS Master functionality
Master Function Call Modicon ® Register Table
readCoil*, readCoils,
writeSingleCoil, writeMultipleCoils
0:00000
readDiscreteInput*, readDiscreteInputs 1:00000
readInputRegister*, readInputRegisters 3:00000
readHoldingRegister*,
readHoldingRegisters,
writeSingleRegister,
writeMultipleRegisters,
maskWriteRegister, readWriteRegisters
4:00000
* - for command interpreter only
Table 12-2: MODBUS Master Object Data Access functionality
Maestro Software Manual Ethernet/IP Communication
MAN-MASSW (Ver. Q)
12-3