That could be done by using PLC jobs. When M10.0 is set you fill special area in PLC called job mailbox (you must configure it on OP in Area Pointers tab too). This area is 4 words long.0-th byte must be 0, 1-st byte contains PLC job no (51 in your case). When screen select would be done, 0 would be transfered in that byte by OP. 2-7 bytes contain job-specific information. In your case bytes 2&3 - screen number, 4&5 - reserved, 6&7 - field number.
Please refer to standart help on PLC jobs for more details.