Evening,
Do RX50 schematics exist on bitsavers, fiche, or elsewhere? I have one
here and it doesn't appear to work. Testing is showing either a busted
motor or something wrong in the voltage control stuff.
Thanks!
Oops. Just found 'em up on bitsavers. Let's hope it's helpful with test
point values. I have no idea if TP1 should be 2.4008VDC or it should be a
specific waveform.
I took a look at the schematics. Something around 2.5VDC looks reasonable
for TP1 when nothing much is happening, because of the potential divider
formed by R2 and R3.
I guess you have already checked that the motor is free to turn?
It looks like the motor is probably connected between J11 pins 3 and 4. Do
you have more than a few volts DC between those pins?
It looks MPWR (connector J4 pin 3) is the signal to tell the motor to run.
You should have something over 0.7VDC here for the motor to run.
What have you got at TP4 - you would need a few volts here too.
What about TP5? It should be 0V when the motor is stopped and a small DC
voltage when it is running. If there is more than half a volt or so here,
check whether R15 is hot.
Regards,
Peter Coghlan.
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Hello!
It'll work. But you need to worry about the timing.....
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Gregg C Levine gregg.drwho8 at gmail.com
"This signature fought the Time Wars, time and again."
On Wed, Jan 1, 2014 at 8:41 PM, Cory Smelosky <b4 at gewt.net> wrote:
On Wed, 1 Jan 2014, Cory Smelosky wrote:
Evening,
Do RX50 schematics exist on bitsavers, fiche, or elsewhere? I have one
here and it doesn't appear to work. Testing is showing either a busted
motor or something wrong in the voltage control stuff.
Thanks!
Oops. Just found 'em up on bitsavers. Let's hope it's helpful with test
point values. I have no idea if TP1 should be 2.4008VDC or it should be a
specific waveform.
--
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects
On Wed, 1 Jan 2014, Cory Smelosky wrote:
Evening,
Do RX50 schematics exist on bitsavers, fiche, or elsewhere? I have one
here and it doesn't appear to work. Testing is showing either a busted
motor or something wrong in the voltage control stuff.
Thanks!
Oops. Just found 'em up on bitsavers. Let's hope it's helpful with test
point values. I have no idea if TP1 should be 2.4008VDC or it should be a
specific waveform.
--
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects
Evening,
Do RX50 schematics exist on bitsavers, fiche, or elsewhere? I have one
here and it doesn't appear to work. Testing is showing either a busted
motor or something wrong in the voltage control stuff.
Thanks!
--
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects
On 2014-01-01 21:32, Jerome H. Fine wrote:
>Johnny Billquist wrote:
In M+ the ability is even better, as device driver loading and
unloading is not related to devices being online or offline.
RT-11 has the same ability. A hard drive can be online
without the device driver being LOADed. If a background
program requests access to a drive, the program can perform
a temporary .FETCH to bring the device driver into memory
and then .RELEASE the device driver when finished. A system
job can't request RT-11 to perform a FETCH, so any disk
drive needed by the program must have the device driver
LOADed before the program uses the disk drive. In theory,
a system job could pause and the user could then LOAD
the device driver just before the system job uses it. MACRO-11
always attempts a .FETCH when a device driver is not already
LOADed.
Ah! Now I know what you are talking about. It's the same in OS/8.
And no, this is not at all the same thing as in RSX.
(If I have things wrong here, I apologize, since now I'm going to make a comparision between RSX and OS/8, and assume that RT-11 indeed do work the same.)
A FETCH loads a device driver from disk into memory. It's an operation you do before performing any I/O to the device. However, you can only fetch a device driver that is known to the OS. The device driver is installed by a different process, which just makes the system aware that the driver exists. You also get some sort of handle in return from a fetch, which is what you use to do I/O to the device.
In RSX, LOAD means installing the device driver into the running system. Prior to the LOAD command, RSX have no clue that the device driver exists. You never have a device driver as a part of your own address space, and several tasks can do I/O to a device concurrently.
When a device driver is loaded into the system, all device driver databases are populated, and the actual code get put somewhere in memory. Don't care where. The LOAD command do that fiddling, and the device driver databases holds enough information that the OS then can invoke the driver when needed. LOAD is a user command, which do a lot of complex operations, and is not something any program ever do on its own. It's a user initiated operation to install a (new) device driver into a running system.
However, for I/O to actually go through to the device, it must also be online.
Online can mean *two* things. The physical device itself (which is what you talk about, Jerome) must obviously be online. But the device must also be online from the driver point of view, which is a separate question. You can load a device driver in RSX, but if a physical device is not present to match it, the device driver will be offline, and any I/O to it will fail before it even comes to the device driver code.
If a physical device later comes online, the driver database does not necessarily become updated to be online. So you can have a physical device online, but still have the device driver offline, but loaded.
Unloading a device driver in RSX means that the driver code is removed from memory, the device driver database marks the device as offline, and that's it. Any memory used by the device driver is freed, so it can be used by other things, such as programs. However, the device driver database is not removed. It's not feasible to remove all possible references to the database.
So, in RSX, all programs can always do I/O to *all* devices known to the system. And without any special preparations or setups. LOAD is for adding even more devices to the known list.
(all within the restrictions of protection and device allocation, of course, which can restrict access)
Not sure exactly what your distinction between unload and remove is.
In RSX terms, you LOAD and UNLOAD device drivers. In 11M, an implicit
online of a device is done when you load it, and offline is done on a
device before unloading it. In M+ the offline and online steps are
separate commands, which just requires that a device driver is loaded.
In RT-11, a device driver must be INSTALLed and the
name placed into the Permanent Physical Device Table
before a LOAD can be performed. The INSTALL code
checks that the device driver is compatible with the
operating system parameters, among other things. A
user may then UNLOAD and REMOVE (in that order)
a device driver if a different version of the device driver
is needed, such as for testing a new version.
Yes, I see where you are coming from now. So, the RSX LOAD (which is done on the running system) is actually equivalent to the INSTALL in RT-11. There is no equivalent to the RT-11 LOAD, all devices are always available.
Even more fun is M+ is that device drivers do not need to be
recompiled if you recompile the kernel. Device drivers are totally
independent of the kernel.
Likewise in RT-11. In fact, I believe RT-11 has always
been that way.
Remember, I'm talking about the equivalent of RT-11 INSTALL here... Ie, I can do a SYSGEN, and build a totally new RSX system, but still use a device driver from a previous SYSGEN just fine. Even though the new kernel have different stuff compiled in, and databases and routines have moved to different addresses.
In respect of RSTS/E, is this possible as well or does RSTS/E
have the same requirement as TSX-Plus?
I think RSTS/E is less flexible, from what I can remember.
TSX-Plus is similar. All device drivers must be LOADed and
permanently resident at boot time.
So, how is it with RT-11. Can you INSTALL a new device driver into a running system and use it, without performing a reboot?
Johnny
On 2014-01-01 16:36, Lee Gleason wrote:
On the 11/74 you more or less had this, in the form of hotplugging
whole bus segments. One a bus segment was disconnected, you could
power it off, and remove controllers if you wanted.
This reminds me of a conversation I overheard at an RSX Magic Session,
at a DECUS symposium in the 80s. A customer was asking Brian McCarthy, a
noted RSX developer, a lot of questions about the legendary 11/74 and
the RSX11M+ additions that had been made to support it. They were
discussing the multiple Unibuses (Unibusen? Unibeese?) and the software
that controls them. The user pointed out that the three letter task name
for the Host Reconfiguration Task (HRC...) was a little tortured - it
would have made more sense to be HRT. Brian said that internally they
had called it Hercules, and HRC was the three letter abbreviation they
chose for it. The user asks, "Why Hercules?". Brian said that it took a
Hercules to wrestle the three headed dog that was the device
configuration databases involved into submission.
I think I've heard the story before. Pretty much the same thing. It would be nice to talk with Brian at some point...
And I totally understand. HRC is very complex and capable. Managing that flexibility at runtime is impressive. Current mP systems usually can not do it the way RSX can (could). There is only one thing that is tied to a specific CPU in RSX. Everything else can be done on any CPU. And that one thing is the updating of the system clock. That is done by the boot CPU. However, if the boot CPU is taken offline, I believe that task is migrated to another CPU, but I would need to check.
Johnny
>Johnny Billquist wrote:
>On 2014-01-01 14:19, Jerome H. Fine wrote:
>Johnny Billquist wrote:
RSX can boot from virtual devices.
Also, you can load and unload device drivers in RSX, but you don't
normally do that just to bring devices offline or online. That is a
separate operation from loading and unloading device drivers. But yes,
if you want to disconnect devices, buses, CPUs or memory, you can do
that just fine on a running RSX system. And bring them online again
later, if you want to. Any other trick you'd like to do? :-)
While it is extremely unlikely that I will ever run RSX-11, the
above ability surprises me. Please clarify to make sure that
I understand. It is my impression that RSX-11 requires
all device drivers to be LOADed at boot time and always
be kept LOADed. TSX-Plus has this requirement and I
guess I assumed that RSX-11 was similar.
Based on your information, I understand that RSX-11 does
support a device driver UNLOAD and REMOVE commands
(or whatever syntax is used in RSX-11 since I just used the
RT-11 syntax). So please confirm.
Yes. That is correct. You can load and unload device drivers at runtime. That is actually a very important design feature in RSX.
So your understanding about RSX have been totally wrong.
Device drivers that are currently in use can not be unloaded, however. Which means that the boot device can't be unloaded, for instance.
YES!! RT-11 has the same requirement. Sort of obvious to
anyone who actually uses the operating system.
In M+ the ability is even better, as device driver loading and unloading is not related to devices being online or offline.
RT-11 has the same ability. A hard drive can be online
without the device driver being LOADed. If a background
program requests access to a drive, the program can perform
a temporary .FETCH to bring the device driver into memory
and then .RELEASE the device driver when finished. A system
job can't request RT-11 to perform a FETCH, so any disk
drive needed by the program must have the device driver
LOADed before the program uses the disk drive. In theory,
a system job could pause and the user could then LOAD
the device driver just before the system job uses it. MACRO-11
always attempts a .FETCH when a device driver is not already
LOADed.
One aspect of the FETCH is that for a Mapped version of
RT-11, the code can be placed in an address which is not
allowed for LOADed device drivers. This often takes place
when a background job is executed as a virtual job under
the program VBGEXE and the Low Memory from 1000
octal to 40000 octal is then available. At least a stub of
all device drivers much be in Low Memory even if the
device driver also uses Extended Memory (one of the
other things that INSTALL does is to set up the Extended
Memory portion of any device driver).
Not sure exactly what your distinction between unload and remove is.
In RSX terms, you LOAD and UNLOAD device drivers. In 11M, an implicit online of a device is done when you load it, and offline is done on a device before unloading it. In M+ the offline and online steps are separate commands, which just requires that a device driver is loaded.
In RT-11, a device driver must be INSTALLed and the
name placed into the Permanent Physical Device Table
before a LOAD can be performed. The INSTALL code
checks that the device driver is compatible with the
operating system parameters, among other things. A
user may then UNLOAD and REMOVE (in that order)
a device driver if a different version of the device driver
is needed, such as for testing a new version.
Even more fun is M+ is that device drivers do not need to be recompiled if you recompile the kernel. Device drivers are totally independent of the kernel.
Likewise in RT-11. In fact, I believe RT-11 has always
been that way.
Also, file systems are also separate, and handled by something called an ACP, which is a separate task. This means that you can have different types of file systems on different disks.
ACPs hook into device drivers, but device drivers have no clue about ACPs.
Not available in RT-11 except maybe as part of the actual
user program.
In respect of RSTS/E, is this possible as well or does RSTS/E
have the same requirement as TSX-Plus?
I think RSTS/E is less flexible, from what I can remember.
TSX-Plus is similar. All device drivers must be LOADed and
permanently resident at boot time.
Jerome Fine
From: "Lee Gleason" <lee.gleason at comcast.net>
multiple Unibuses (Unibusen? Unibeese?)
"Unibi".
The
user asks, "Why Hercules?". Brian said that it took a Hercules to wrestle
the three headed dog that was the device configuration databases involved
into submission.
Nice. Well I guess if TGHA makes sense ("The Great Heuristic Algorithm" --
um, for spare columns in ECC memory, right?), this makes a lot more sense...
John Wilson
D Bit
From: "Jerome H. Fine" <jhfinedp3k at compsys.to>
In respect of RSTS/E, is this possible as well or does RSTS/E
have the same requirement as TSX-Plus?
RSTS doesn't have loadable drivers, so it all has to be genned into the
system (and user-written drivers aren't officially supported). On the plus
side, RSTS autosizes the system on every boot (including floating CSRs, and
all vectors except card readers are autodetected so they don't need to follow
the rules at all -- user-written drivers would have to be hooked up to this
too), and passes CSR/vector/model information to the drivers that it enables.
So while RSTS requires the drivers to be linked to the system, it's not a
totally rigid mass that works only on the exact config it was built for.
You can run a monitor on totally different hardware and as long as it has
drivers for enough of the existing peripherals to work, you're all set.
Also, you can have multiple monitors (built different ways) on the same
pack and tell the pre-boot thingy (INIT.SYS) which one to boot.
John Wilson
D Bit
On the 11/74 you more or less had this, in the form of hotplugging whole bus segments. One a bus segment was disconnected, you could power it off, and remove controllers if you wanted.
This reminds me of a conversation I overheard at an RSX Magic Session, at a DECUS symposium in the 80s. A customer was asking Brian McCarthy, a noted RSX developer, a lot of questions about the legendary 11/74 and the RSX11M+ additions that had been made to support it. They were discussing the multiple Unibuses (Unibusen? Unibeese?) and the software that controls them. The user pointed out that the three letter task name for the Host Reconfiguration Task (HRC...) was a little tortured - it would have made more sense to be HRT. Brian said that internally they had called it Hercules, and HRC was the three letter abbreviation they chose for it. The user asks, "Why Hercules?". Brian said that it took a Hercules to wrestle the three headed dog that was the device configuration databases involved into submission.
--
Lee K. Gleason N5ZMR
Control-G Consultants
lee.gleason at comcast.net
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