Modicon

Modicon

Another blast from the past, MODBUS adapters.

@6C3A.adf "Modicon MC984 Programmable Controller Adapter" [MODBUS Plus]
@6C3B.adf "Modicon SM85/Modbus Plus Adapter"

DOSMBP13.ZIP MODBUS+ DOS Device Driver ver 3.43
OS2MB211.ZIP MODBUS+ OS/2 Device Driver ver 2.11

Modicon Modbus Plus Network IBM Host Based Devices User's Guide
984 Programmable Logic Controllers and 800-Series Input/Output Modules
Modicon 984 Programmable Controller Systems Manual

MC-948 vs SM85

Modicon MC-984 Programmable Controller Adapter [AM-0984-MC0]

This adapter is a full PLC, not just a communications link.

Older boards might use a 1/3N 3V lithium battery.
Crystal Clock Jumper Leave jumpered at all times.
RIO Terminator Jumper The 75 ohm terminator resistor jumper.
   Pins 2-3 terminator resistor is connected.
   Pins 1-2 terminator resistor disconnected.
RIO Shield-To-Chassis jumper
   Pins 2-3 RIO Cable shield isolated from chassis GND by a capacitor.
   Pins 1-2 RIO Cable shield connected to chassis GND.

Modicon MC-984 Rear Panel

F–Connector for RG6/U RIO Cable

Modbus Plus Status LED Patterns

LED Pattern	Indication (Status)
Six flashes/second	Normal operating state - successfully receiving and passing the token. All nodes on healthy network flash this pattern.
One flash/second	Node is off-line just after power-up or after exiting the four flashes/second mode. In this state, the node monitors the network and builds a table of active nodes and token-holding nodes. After being in this state for 5 seconds, the node attempts to go to its normal operating state (indicated by 6 flashes/second).
Two flashes, then OFF for two secs	Node hears token being passed among other nodes, but it never receives token itself—check network for an open circuit or defective termination.
Three flash, then OFF for 1.7 sec	Node is not hearing token passing among other nodes. It periodically claims token but cannot find another node to which to pass it. Check network for an open circuit or defective termination.
Four flashes, then OFF for 1.4 sec	Node has heard a valid message from a node using a network address identical to its own address. Node remains in this state for as long as it continues to hear the duplicate address. If duplicate address is not heard for 5 seconds, the node changes to one flash/second mode.

Modicon SM85/Modbus Plus Adapter [AM-SM85-00x] -001/Single, -002/Dual