1766-RM001A-EN-P MicroLogix 1400 Programmable Controllers ...

420 Communications InstructionsMessage Type File Type Element Size Maximum Numberof Elements per MessageModbusCommandsB, N (command 5) 1-bit 1B, N (command 6) 1-word 1B, N(commands 1, 2, and 15)B, N(commands 3, 4, and 16)1-bitmulti-register1920 Modbus bit elements(120 words)(Commands 1 and 2 are readonly, 15 is write only.)120 Modbus register elements(120 words)(Commands 3 and 4 are readonly, 16 is write only.)(1) Message Type must be 500CPU or PLC5. The Local File Type and Target File Type must both be Floating Point.Publication 1766-RM001A-EN-P - October 2008