Hi @matthewd92 a=socket_read_asci_float(6)b=aSometimes i did not receive a from socket so it shown as '?' which defines 'not a number' i think. Please refer attachments of errors. When i wanted to run the program, i have to go and make it zero manually in order to run. How to make it as zero when i receive such errors. Note:i cannot use previous program values for some reasons.