Additional UNITs from 4 up to 254 are replicated from Unit 0.
If the UNIT->uname has already been populated, we could leak memory if
it isn't released before copying from the template UNIT.
At this time:
- The ZAP command exists to remove meta data from containers that
have it. Container files processed by the ZAP command will generally
be restored to the size it was before the addition of the meta data
and the file time stamps will be unchanged.
- Newly created containers get meta data.
- At attach time, containers that don't have meta data, but have
recognized file systems that fit within the drive it is being
attached to get meta data added without changing the file timestamps.
- Containers that don't have meta data and don't have a recognized
file system that is <= the drive size are attached without comment
and without adding meta data as long as the drive is NOT set to
autosize (controllers that support multiple drive types all default to
autosize, which can explicitly be disabled on a drive by drive basis).
- Containers that don't have meta data which are > the drive size can
only be attached read only.
- Containers with meta data can not be attached to a different
controller at all if the container size is smaller than the drive on the
other controller.
- Containers that have meta data can be freely be attached to the
controller that they were attached to when they got the meta data.
If a file system is detected, it will be reported. Otherwise if no
recognized file system is found, the attach will be silent. File
system detection reporting can be suppressed with -Q on the attach
command.
- Containers with meta data can only be attached read only to a different
controller if the container is larger than the drive it is being
attached to.
In the future:
- In general, containers with meta data (or recognized file systems)
will be attachable to MSCP and SCSI controllers, as long as reasonable
sector sizes and file system not requiring interleaving have been found.
- Containers without meta data will only be attachable if autosize
is disabled and the container is <= the size of the drive.
- Explicitly setting a drive type on a unit will implicitly disable
autosizing. If a user wants to set the default drive for a unit
and still allow autosizing they must explicitly set the unit to
autosize after setting the drive type.
Relevant to: #1065, #1059, #1094, #1100, #1118, #1117
Historically this functionality was reimplemented within each
DEVICE simulator often with slightly different implementations
and inconsistencies. Solving this globally within SCP required
changes in many places, but should henceforth be reasonably
managed.
As discussed in #1034
- Make all PDP11, VAX RP and RQ devices autosizing behave similarly
- Generalize the attach help to be specific to the device/system being
attached
- Remove the sim_disk_pdp10_* calls which weren't correct or needed
since sim_disk_attach_ex provides sector size which is used correctly
Array REGister definitions have been made consistent by passing the
name of the array object. This allows proper sizing assessment
to occur in the register validation logic.
Some previously described array REGister initializers were not really
arrays. Some were structures and others were merely pointers to
someplace in memory that it was desirable to view as a scalar array.
Structures or other blob data should now use SAVEDATA. Virtual
arrays intended to be interpret some part of memory as scalar data
now use VBRDATA initializers.
Array REGister definitions have been made consistent by passing the
address of the whole array object. This allows proper sizing assessment
to occur in the register validation logic.
- Extra queue and timer units on RQB, RQC, and RQD are now properly
initialized.
- PDP11 unit numbers are numbered:
device RQ 0-3
device RQB 4-7
device RQC 8-11
device RQD 12-15
Some devices have dedicated units that perform various independent
functions (often timing) that are independent of the primary device unit
which is ATTACHed. This services to help interpret debug information
that may be produced.
These changes facilitate more robust parameter type checking and helps
to identify unexpected coding errors.
Most simulators can now also be compiled with a C++ compiler without
warnings.
Additionally, these changes have also been configured to facilitate easier
backporting of simulator and device simulation modules to run under the
simh v3.9+ SCP framework.
The RSX-11M+ boot driver expects a slower response from the simulated
UDA50 controller. This response is only in during the MSCP initialization
sequence, so normal protocol interactions for read and write I/O are
unchanged. Updated value determined by John Forcast. Fixes#216.
Vector values contained in device information blocks are the true bus relative vector values. CPU specific biased vector values are produced by the respective vector fetching logic and vector values are limited to 9 bits with <1:0> = 0 as specified in both the Unibus and Qbus documents.
Here's a PDP11 SIMH bug as old as the simulator itself: the reset_cpu routine sets the PS to 340 (interrupts disabled). This causes some versions of Lunar Lander not to work. In fact, the initial state of the PS is not architecturally standardized:
04: cleared (from schematics)
05: cleared (from manual)
20: cleared (from schematics)
34: cleared (from schematics), set to 340 on boot?
40: cleared (from schematics)
44: cleared on init, set to 340 on boot (from schematics, manual)
45: cleared (from schematics)
60: cleared (from schematics)
70: cleared (from schematics)
T11: set to 340 (from spec)
LSI11, F11: 4 mode behavior (from memory on power recovery, cleared on GO, 340 on boot, mode 3 undefined)
J11: 4 mode behavior (from memory on power recovery, cleared on GO, 340 on boot, 340 on jump to custom PROM)
The story seems to be this. All non-VLSI PDP11s used TTL chips to implement the PS, either discrete flip-flops, or 4b registers, or both.
Starting with the first system, the 11/20, they were wired clear on the processor INIT signal (power-up or front panel START switch), so that all internal state started as 0. This worked fine, because START also reset the Unibus and cleared all interrupt enables. So even though the processor was as IPL = 0, no interrupts were possible. Then along came the LSI11...
The LSI11 implemented a line-time clock with NO INTERRUPT DISABLE. Thus, if IPL was left at 0 and a bootstrap routine from a slow device was started (e.g., a floppy drive), the clock would tick, and an interrupt would occur, before the bootstrap routine finished. Because no vectors were set up, the processor would crash. So the LSI11 started the practice, carried over to all later PDP11 VLSI chips, of setting the PS to 340 before jumping to a boot ROM.
The T11 did this in all modes of startup, because its only startup behavior was to jump to a "boot" routine. It did not have a console of any kind.
Accordingly, it appears that the cpu_reset routine needs to set the PS based on the processor model. Further, all boot routines need to set the PS to 0 or 340 based on the processor model. (It's probably safe for boot routines just to set the PS to 340, but it's not technically
accurate.)
