CM11A does not get ready for X10-trasmission with Programmable Logic Controller

["dca" <d-anton@xxxxxxxxx>]

I am trying to control an X10 installation from a Programmable logic
controller (PLC S7-200) via a CM11A.
For test purposes there are only A2 (AM12) and A5(LM15) installed.

The following work without any problem:
-Get status 8BHEX
-Write time 9BHEX
-X10 reception (5AHEX from CM11A) and subsequent response C3HEX to receive
serial data buffer
(Note: I occcasionaly used TM13 (as A1) and a remote control unit to trigger
the serial ring on CM11A)


However when  I try X10 transmission the following happens:

PLC                                      CM11A

046eHEX
//address A2
                                            72HEX
//checksum ok
00HEX
//  acknowledge
                                             00HEX
// not OK, ought to be the expected 55HEX


if one continues with the function
0662HEX
//function A On
                                            68HEX
//checksum ok
00HEX
//  acknowledge
                                             00HEX
// not OK, ought to be the expected 55HEX

and A2 remains Off.

Just in case, I changed the CM11A with a brand new one. To no avail.

Both the CM11As work fine with the ActiveHome AND HomeSeer software on my
PC.

I would be grateful for any suggestions.
Many thanks in advance

dca