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Entry type: FAQ Entry ID: 40009, Entry date: 03/18/1996

Which AS511 special driver of the STEP 5 - PG software should be used by preference when implementing the teleservice hardware solution (TK858 in set

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In teleservice couplings with the TK858 telecommunications device, it often happens that the message "PLC time overrun" is displayed on the PG during data exchange and the operating mode is set back from On-line to Off-line. This happens when large volumes of data or blocks are to be transferred. This might be due to timing problems of the AS511 standard driver in conjunction with TK858.

When implementing the TK858 in the teleservice set-up, it is necessary to use the AS511 special driver offered instead of the AS511 standard driver. Which special driver to use depends on the COM interface used (COM1 or COM2) and the STEP 5 version. One of the following drivers can be selected.

STEP 5 PG SOFTWARE: Recommended AS511 driver:
STEP 5; Level 5, Version 3.0 to 3.2AS511 standard; as required AS511 special drivers 1-3 for COM1 interface and AS511 special drivers 4 and 5 for COM2.
STEP 5; Level 6, Version 6.3This version of STEP 5 software has not yet been officially tested in conjunction with TK858 and released. It is generally recommended to implement a special driver.
STEP 5; Level 6, Version 6.5 and higher The new AS511 special drivers 6 (COM1) and 7 (COM2) are integrated in the STEP 5 software as from Version 6.5. They are to implemented primarily in conjunction with TK858.

Refer to your STEP 5 documentation for how to select and set up the special drivers.

Information on AS511 special drivers.

The baud rates for the individual drivers given in the selection mask of the AS511 special drivers have nothing to do with the baud rates set on TK858 or the modems. These baud rates refer to the monitoring time of each of the selected COM1 or COM2 interfaces on the PG/PC.

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