>On many of the operating systems, you don't have to do a SYSGEN - just
>tweak a number in the configuration word and viola, it's now a 50Hz
>machine.
>
>For an RT-11 machine, in particular, you can tweak this on a running
>system if you wish:
[... 50hz.mac deleted ...]
Tim - I'm surprised at you... simply setting this bit is *not* sufficient.
The bit is set based on assembly parameters. Those parameters also
set the values for ticks/day based on 50 and 60 hz. Those values are
patched at boot time to reflect what the system thinks the clock is
supposed to be (what it was genned for).
Without the other counters set correctly, date rollover won't work
at all correctly... since it will be waiting for sufficient clock
ticks at the 60hz rate to have gone by before it bumps the clock.
I seem to recall that there is another gotcha to this, but haven't
yet found it in the sources...
Bottom line is that the config bits are supposed to be read, not
written, as they indicate what the system was built for or what it
has determined (via probe) to be running on...
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
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Received on Mon Mar 27 2000 - 08:33:31 BST