CE039 FAQ

I have a CE039_12V, 4 channel, rs232 relay board.
Are the commands ASCII text strings or hexadecimal bytes?
Do you send the command string with or without spaces "55560000000102AE" or "55 56 00 00 00 01 02 AE"?
Is there a carriage return and/or line feed or something else at the end of the command string?
Thank you.

HEX format ， "55 56 00 00 00 01 02 AE" 
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