MODBUS RTUMaster/Slave Communication8-88.3.3 RECV Instruction (MODBUS Function Code Unspecified Type) Instruction format OperandItems Settings Setting rangei Specify the operation unit. US / SSS1 Specify the partner station no. H1 - HF7 (1 - 247)S2 Specify the device initial address of the source node data area in thepartner node.H0 - HFFFF (0 - 65535)(Note 1) (Note 2)n Specify the No. of sent data.1 - 127 words1 - 2040 bits(Note 3)D1 Specify the device initial address of the receiver node data area in thesource node. (Note 1) (Note 4)D2 Specify the device area in the source node to save the execution resultcode (one word). (Note 5)(Note 1) Types of devices and transmission methods to be specified for operands [S2] and [D1], and MODBUSfunction codes to be used for instruction execution vary.Device to be specifiedfor [S2] and [D1]TransmissionmethodMODBUS function codesto be used for instruction execution16 bit deviceWX, WY, WR, WL, DT, LDRegistertransmissionRead Coil Status (01)Read Input Status (02)Read Holding Registers (03)Read Input Registers (04)1 bit deviceX, Y, R, L, DT, n, LD, n Bit transmission Read Coil Status (01)Read Input Status (02)(Note 2) Bit device L; DT, n; and LD, n cannot be specified for the header of the sender data in the partner node.(Note 3) The No. of sent data is on a word basis for register transmission, and on a bit basis for bit transmission.(Note 4): Device that can be specified for D1 are: WX, WY, WR, WL, DT, LD.(Note 5): Device that can be specified for D2 are: WX, WY, WR, WL, DT, LD. Saved as one word in the specified area.0: Normal completion1: Communication port is being used for master communication2: Communication port is being used for slave communication3: No. of master communication instructions that can be used simultaneously has been exceeded4: Sending timeout5: Response reception timeout6: Received data errorPhone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
