@Bernard Hi.
To retrieve only the day of the week, you can use the RTCF parameter as such:
"|RTC UID:rtc0 HID:rtc RTCF:dddd\r\n"
You can also use abbreviation:
RTCF:ddd
or numerical form with leading zero:
RTCF:dd
or without:
RTCF:d
For more information about formatting, see the manual, Appendix C (Supported date and time formats).
Note: The formatting does not support spaces, so you need to use e.g., underscore or hyphen or similar to build your own timestamp.
Best regards,
kl3m3n