M.8.3 Check COM1/COM2/LAN

Check the send and receive lines for RS-232C, RS-422 and network communication. Use this check when an error occurs.

When checking RS-232C and RS-422, you need to connect the SIO cable.

Preparing the loopback cable

You need to prepare a loopback cable to check COM1/COM2/LAN.

There are four patterns to wire the loopback cable, which differ depending on the display unit.

Display Unit

Loopback Cable Types

GP3000 series (except for GP-3302B)

Pattern 1

GP-3302B

GP-4200 series (except for GP-4203T)

GP-4300 Series

GP-4400 Series

GP-4500 series (except for the GP-4503T MPI port)

GP-4600 series (except for the GP-4603T MPI port)

ST3200 series (except for AST-3211A MPI port)

ST3300 series (except for AST-3302B MPI port)

ST3400 series

ST3500 series

Pattern 2

GP-4100 series (except for GP-4104 and GP-4107)

Pattern 3

LT4000 Series

Pattern 4

Pattern 1

Pattern 2

Pattern 3

Pattern 4

Check

Connect the loopback cable to one of the interfaces and check the operation. When the operation is acceptable, [OK] is displayed. When there is a problem, [NG] is displayed.

  1. Go to offline mode and touch [Maintenance Menu] on the item changeover switch.

  2. [Maintenance Menu] screen opens. Touch [Check COM1/COM2/LAN].

    • When using GP-4100 series, touch the [Check COM] or [Check LAN] button and go to step 4.

  3. [Check COM1/COM2/LAN] screen opens. Select the interface to check. (Example, COM1/RS232C)

  4. As prompted by the displayed message, touch [Start].

  5. When there is no problem, [OK] is displayed. When an error occurs, [NG] is displayed. Touch [Close] to end the check.