Ascii to Real Conversion in Siemens PLC S7 - 300

Dear Experts.

I have a CPU 315-2dp Siemens PLC which is communication between mistubishi fX-3U Series

mistubishi is giving me AScii String data which is actually some real value
i wanted to show this value on hmi

please let me know if there is any conversion meathod in siemens.

See the standard library:

Don't forget that Siemens uses a non-standard (not IEEE) format for their floating point notation. You may need to play around with your ASCII String to get it into the correct format for the conversion (probably by adding a couple of zero's to get the number of digits after the decimal point up to the required 7).