>RT11 will run in more than 256k (mine has 2mb). The RLV11 however limits
>you to 256k, though you could write your one handler... nah.
It doesn't really limit RT-11... what it does do is require that
any I/O transfers must occur entirely in the low 256kb of memory.
This would require you to ensure that all programs which are going
to do I/O to the device have their user buffers in the low 256kb
of memory.
As for writing your own handler... you could instead make modifications
to the DL handler such that it 'trampolines' the data from a user
buffer anywhere in memory to a system buffer (maybe in the handler)
which is assured to be in the low 256kb, and do the transfer from
there...
That is a technique which other OSes have done to take care of the
problem...
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
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Received on Sat Apr 03 1999 - 21:45:28 BST