CID Action
1416081 changed variable answer to int
1416082 checked returned values with ASSURE - read error means corrupted target code.
1416088 added return
1416109 This fallthru was intentional - duplicated code to make coverity happy
1416111 This fallthru was intentional - duplicated code to make coverity happy
1416116 This fallthru was intentional - duplicated code to make coverity happy
1416117 This fallthru was intentional - duplicated code to make coverity happy
1416124 protected against negative return
1416142 added ASSURE, however this case won't happen since reg_intpending==true implies positive int level
1416145 checked non-NULL, return SCPE_ARG if NULL
1416150 since only 2 drives are supported, fdc_selected is decoded to 0 and 1 only (allowed 2 and 3 before)
1416152 restrict to 2 drives only
1416166 checked value with ASSURE
1416101 typo: should have been resx
1416106 unnecessary code removed
1416110 this fallthru was intentional - duplicated code to make coverity happy
1416112 this fallthru was intentional - duplicated code to make coverity happy
1416148 change condition to check for negative value
1416179 break was remainder from former logic - removed
1415866 code was remainder from former unimplemented instruction trap - removed
the opcode table first word consists of bits:
<7> = FPD is legal for this opcode.
<4:6> = number of specifiers for unimplemented opcodes (VAX subsets)
<3> = unused
<0:2> = number of specifiers
The mask used to be 0x70. The convention is that x_M_y is a mask value
<right-justified>, for a macro like:
#define get_foo(x) (((x) >> x_V_foo) & x_M_foo)
For a subset VAX (like the 3900), the unimplemented opcodes are those
Many of the intermediate state variables are captured by the instruction
history mechanism. Make sure that these don't come into and out of
scope between instruction executions.
IPL_UBA already has the subtract built in:
So it shouldn't be extracted again.
The whole routine looks a little strange, but the way it works is
that an interrupt from the UBA itself sets <bit 31> in the returned vector.
Because the vector is read by code and not used by hardware, the flag
bit is "harmless."
UBA interrupts occur only under strange circumstances, like bad map
pages and device NXMs. Under the simulator, with a debugged OS, they
never happen.
For the PDP11, this includes deferring the setting of DONE on an error, allowing RSTS V4 to work correctly.
There was a minor (possibly only theoretical) bug in dt_seterr as well.
dt_seterr is supposed to stop the drive. If the drive is accelerating, at
speed, or stopped, it works fine. But if the drive is decelerating, it did
not clear out the "successor" states. In theory, the drive could be in the
middle of reversing - that is, there are successor states of accelerating
(in reverse) and at speed. So the successor states need to be cleared,
or the drive won't actually stop.
The fifth DECtape controller (the PDP8's TD8E) is much simpler and
doesn't have the problem.
- Fix protect fault for 2-word instructions so that background tasks do not
crash.
- Lay the ground work for supporting the enhanced instruction set.
- Fix disk layout bug (disks are no longer compatible with previous version).
- Add debugging support for displaying MSOS 5 system requests.
- Fix bugs found by Coverity.
The code wasn't handling interrupts correctly when TCCM was written. In
particular, if the GO bit clears DONE, the code looked for the "SET IE" case
too soon and didn't clear the interrupt that was incorrectly generated.
The new code factors "GO" into the calculation.
