DL2000-ASM
ASCII Serial Interface

A Solution to the Missing ASCII Port on the ControlLogix System

The DataLink DL2000-ASM communication controller can send ASCII data to the processors via a 1756-DHRIO Module providing a solution for ControlLogix applications needing an ASCII port. All parameters are user-configured, including the PLC's station number, the DL2000-ASM's station number, and the PLC's destination data table address.

Earlier this year an A-B user asked us to find a way to interface their ASCII devices to ControLogix via Data Highway Plus and Remote I/O. We came up with the solution: the DataLink DL2000-ASM, ASCII Scanner Module.

Application:
Mathews Conveyor's customer, Circuit City, required a solution that would interface their PSC Surescan ASCII devices to A-B ControLogix over Data Highway Plus. Mathews currently has 15 of these configurations installed with 3 more pending applications at Circuit City.

Application Details:
PSC Surescan scanners are connected via RS-232 to the serial port of the DL2000-ASM (station 12 on the DH+ network in this application). The Surescan devices transmit ASCII messages terminated with a "CR" (Carriage Return) to the DL2000-ASM. The ASM, user-configured to send data to File 38 starting at Word 0, then passes the data to the ControlLogix via a 1756-DHRIO Module* (station 11 in this application). A "PLC Map" is configured in the ControlLogix processor to map file 38 to an array named "Scanner," where the data is stored. In the processor, however, data is not displayed in ASCII format and is therefore sent via another DH+ port to a host computer for data manipulation. 

* Data Highway Plus traffic is treated as "unscheduled data" in the ControlLogix processor.  For this reason, it may be necessary to change the processor's setting for how much time it allocates to unscheduled data.

Custom Protocol Conversion:
Since 1993, DataLink Technologies, Inc. has been providing A-B customers with custom protocol development for A-B Networks.

Coming Soon:
-Remote I/O Scanner (Master): A new way to interface your SoftPLC 
-PC/104 Modbus Plus interface card.