PLC-5 L/20E, L/40E, L/80E direct All PLC-5 processors connected through DH+ via the 1756-DHRIO module. The valid range for the 1756-DHRIO slot number is between 0 and 16 but depends on the chassis size. The 1756-DHRIO channel is either 2 for channel A or 3 for channel B. The DH+ node number range is from 00 to 77 octal. See the ControlLogix Ethernet Communication interface Module User Manual for more information. Example: O:0/5 means it is a physical output. There is a couple of ways to show the address of a bit in RSLogix 500. This number is in octal and is the same as configured in the PLC-5 processor. Bit is an address in the PLC and it can be Input, Output, or Internal coil. The final and fourth number is the DH+ node number. The third number is the channel of the 1756-DHRIO module that the PLC-5 processor is connected to. Introduced in 1986, it was the gold standard for industrial control applications for many years and one of the first platforms that could be programmed by a personal computer.
The second number is the slot number of the 1756-DHRIO module of the DH+ network the PLC-5 processor is connected to. Allen Bradley 1771-AL PLC-2 Local I/O Adapter Module 2 Slot Addressing In 2017, the popular Allen-Bradley PLC 5 platform was discontinued by Rockwell Automation.
The first number is always 1 and tells the 1756-ENET module to route through the backplane. The Connection Path format contains 4 numbers separated by commas.
