I can see time and date of the system clock in the greeter message when OF starts on the Alubook. But I haven't found a way to display it actively with a command in OF. It's actually possible to set time and date on the Alubook in OF with
decimal dev rtc sec min hour day month year set-time (eg.: decimal dev rtc 45 23 1 16 7 2021 set-time) (and setting it this way survives a reboot) - just no command that I knew of on how to display it. And yes: it seems the internal PRAM clock battery on this machine is dead. It's easy to display time and date on an older (2002) PowerBook3,5 (Titanium IV) by simply typing time&date in its OF (battery for PRAM seems to be OK on this machine). But this same command on the Alubook just gives me an 'OK' without displaying anything else. Thanks in antcipation, Wolfgang