13 Feb
2000
13 Feb
'00
5:10 a.m.
Megan wrote:
Also, I looked
at the SYSMAC.SML file and note that there is no .DrVTB
macro present (also no .DrSet macro although the information is hard
coded into the various device drivers, and obviously the SET commands do
work). Does this mean, in your opinion (maybe you or someone else
remembers that far back - 22 years ago) that an LS.MAC device driver
can't operate in V3.0B since RT-11 is not yet smart enough to use dual
CSR/VECTOR hardware that requires two .DrAst entries? I notice that V4.0
of RT-11 finally has the LS.SYS device driver, but there is none present
in V3.0B of RT-11, only the LP.SYS device driver.
The .DRxxx set of macros were not
added to RT until about the V4.0
timeframe. If you were to take an LS.MAC from a later release and
modify it in such a way that it did not use .DRxxx macros, and used
what data structures were available in V3B, it certainly would work. From what I can understand, that means that the
essential macros were
already available. While .DrSet would have been helpful, I
can see in
block zero of LPX.SYS that there is a full set (pardon the pun) of SET
options and the LP.MAC file just has them hard coded in place.
The key question I am wondering about is IF the ISR interaction between
the operating system and the device driver that is present in V4.0 of
RT-11 when the LSX.SYS device driver is LOADed and both pair
of CSR/VECTOR are activated (so that XON/XOFF can be allowed
for a serial printer) is also present in V3.0 of RT-11? I do not want to
assume that just because V4.0 allowed two CSR/VECTOR pairs to
be active and a device driver such as LSX.SYS to have two .DrAst
entry points that V3.0 of RT-11 also allows the same thing.
Sincerely yours,
Jerome Fine