From:	SMTP%"leichterlrw.com" 21-MAR-1995 03:51:28.33

Subj:	RE: Sticking MV II cards into a MV3400



	I've got a couple of disk controllers (Emulex QD21 and Dilog DQ686) in

	a couple of MVII's that I want to junk.  I've got access to a MV3400

	and was wondering if the Q-bus backplanes are different on these

	systems.  I realize that the mounting equipment is different (MVII's

	in BA23 vs the MV3400 with a BA213), but I can tolerate some

	jury-rigging in this application.



The Q-bus is pretty standard; your boards should work.  The only Q-bus

systems that get a bit odd are on things like the whatever-4000-it-is that

provides a Q-bus interface.  It has some restrictions - but the problems are

in the interface to the rest of the system, not in the Q-bus itself.  Other

than that, unless you have some *really* old Q-18 stuff - well, DEC is pretty

good at designing and specifying buses and the Q-bus was at least their 3rd

generation (after the Unibus and the Omnibus).



							-- Jerry



From:	SMTP%"SMSprovis.com" 21-MAR-1995 04:59:18.20

Subj:	Sticking MV II cards into a MV3400



   One more caution.  While the boards are almost certain to work,

half-size (dual-height) boards must go into the top half of the BA213

backplane (rows A-B).  In the BA123, slots 5 and up have bus continuity

through both halves (rows A-B and C-D), so putting two small boards into

one slot can work.  In a BA23, my old books are not so clear, but the

same may be true for slots 4 and up.  In a BA213, it's one board only

per slot.  Otherwise, it can't miss.  We have mu-VAX IIs (BA123) and a

4200 (BA215 and BA213), and have run several boards in both.  (Moving a

board from a BA[1]23 to a BA21x is easier than going the other way,

mechanically.)



   Getting rid of any 8MB memory boards from your junk mu-VAX IIs?  I

could help.



------------------------------------------------------------------------



   Steven M. Schweda                    (+1) 612-636-8950  (voice)

   Provis Corporation                   (+1) 612-636-8951  (facsimile)

   2685 Long Lake Road                  smsprovis.com  (e-mail)

   Roseville, MN  55113-2537





From:	SMTP%"hoffmanxdelta.enet.dec.com (Stephen Hoffman)" 21-MAR-1995 16:13:02.90

Subj:	Re: Sticking MV II cards into a MV3400





In article <3kl7vg$cpisaba.info.ucla.edu>, ronpisces.fusion.ucla.edu () writes:

:

:I've got a couple of disk controllers (Emulex QD21 and Dilog DQ686) in

:a couple of MVII's that I want to junk.  I've got access to a MV3400 and

:was wondering if the Q-bus backplanes are different on these systems.  I

:realize that the mounting equipment is different (MVII's in BA23 vs the

:MV3400 with a BA213), but I can tolerate some jury-rigging in this application.





  ATTEMPT ANY AND ALL Q-BUS MODIFICATIONS AT YOUR OWN RISK -- CONTACT

  YOUR HARDWARE SERVICE ORGANIZATION FOR FURTHER ASSISTANCE.



  You may (will?) end up with RF emissions and/or RFI problems if the

  enclosure is not properly RF-sealed.



  First, if you are not familiar with working inside the Q-bus enclosure,

  or if you are unfamiliar with the DMA grant continuity, or if you are

  unwilling to make potentially permanent modifications to the card, or

  if you are unwilling to place other cards at risk due to an incorrect

  installation, or if you are unfamiliar with working with static-sensitive

  electronic components, DO NOT ATTEMPT THIS.



  Dual-width cards should install and operate in the upper half of the

  slot in the BA2xx and BA4xx system.



  If it is a quad-width card, what you are considering likely involves the

  electrical modification of a Q22/Q22 card to operate in a Q22/CD slot. 

  (In the BA23 and BA123, these Q22/CD slots are restricted to "memory" and

  "processor" modules, and Quad-width boards can *not* be installed in these

  slots.  The KA640 MicroVAX 3400 processor shipped in a BA2xx enclosure.)



  Quad-width cards may/will cause you problems in the BA2xx or BA4xx series

  Q22/CD enclosures -- you should be aware that a DMA grant continuity etch

  on the lower half of the card is *not* permissible in a CD slot.  (All

  BA2xx and BA4xx series enclosures are Q22/CD in all slots -- most (all?)

  Q-bus cards not intended for use in the BA2xx or BA4xx series will have

  this etch, and it will cause problems.)  If the DMA or Q-bus circuitry

  is connected off the lower etch fingers, you will have real trouble here. 

  If it is "just" the DMA grant continuity circuitry, some surgery on the

  card etch may allow the card to operate in a Q22/CD slot.



  I DO <**NOT**> RECOMMEND MAKING THESE MODIFICATIONS, NOR DO I RECOMMEND

  INSTALLING MODULES IN AN ENCLOSURE THEY WERE NOT INTENDED TO RESIDE IN.

  CONTACT YOUR HARDWARE SERVICE ORGANIZATION FOR FURTHER ASSISTANCE.



  ------------------------------ Opinionative -------------------------------

   Stephen Hoffman, NR EMT-I, WEMT, N1THN        hoffmanxdelta.enet.dec.com

        OpenVMS Engineering, Digital Equipment Corporation, Nashua NH





From:	SMTP%"newsspcuna.spc.edu (Network News)" 21-MAR-1995 21:40:15.23

Subj:	Re: Sticking MV II cards into a MV3400



In article <3kl7vg$cpisaba.info.ucla.edu>, ronpisces.fusion.ucla.edu () writes:

> I've got a couple of disk controllers (Emulex QD21 and Dilog DQ686) in

> a couple of MVII's that I want to junk.  I've got access to a MV3400 and

> was wondering if the Q-bus backplanes are different on these systems.  I

> realize that the mounting equipment is different (MVII's in BA23 vs the

> MV3400 with a BA213), but I can tolerate some jury-rigging in this application.



  Almost all MVII systems (MVII, VSII, VSII/GPX) were delivered in BA23 or

BA123 cabinets. The BA23 is 3 C-D slots followed by Q22 slots, the BA123 is

4 C-D slots followed by Q22 slots. The BA2xx/4xx cabinets used for the later

MicroVAX/VAX systems are only C-D slots. This means that any dual-height

card *must* go in the A-B (usually top) positions in those cabinets. Depend-

ing on the weight of the card and the stiffness of the backplane connectors,

the card may tilt out of its socket. There's a plastic baffle which looks

like a dual-height card that is used to support these cards as well as make

sure the airflow works properly. If you're only moving one dual card it

shouldn't matter.



  You've already observed that the mounting is different (the new systems

are S-box). DEC retrofitted some cards (the KLESI-SA is a regular KLESI

with a S-handle riveted on), redesigned some cards (the CXY08/CXA16/CXB16

are re-layouts of the DHV11/DHQ11 family), and left some cards alone (the

TQK70 is the same board in both cabinets). DEC sells blank S-box fillers

as well as some with cutouts, so you could probably do something that both

looked Ok and maintained the airflow and FCC compliance if you wanted.



  Some boards won't work in the newer CPU's. An obvious example is Micro-

VAX II memory. There are some more subtle issues, though. For example, many

older boards (like the TSV05 controller) and 3rd-party boards didn't work

in KA650/KA655-based systems (3500/3600/3800/3900) due to an error in the

Q-bus interface IC on those processor boards which DEC was very reluctant

to fix. Eventually DEC fixed it - if your system is on DEC hardware support

you should be able to get a new CPU (for the KA650 it's Rev. K1, I think).

If you're not on DEC hardware support, it's probably cheaper to buy a used

CPU on the surplus market (making sure it's up to rev) than to get DEC to

swap it on the time+materials plan. I don't think this affected the KA640

(3300/3400) but I'm not certain.



	Terry Kennedy		  Operations Manager, Academic Computing

	terryspcvxa.spc.edu	  St. Peter's College, Jersey City, NJ USA

        +1 201 915 9381 (voice)   +1 201 435-3662 (FAX)



From:	SMTP%"Info-VAX-RequestMvb.Saic.Com" 22-MAR-1995 16:20:55.54

Subj:	Re: Sticking MV II cards into a MV3400



Stephen Hoffman, NR EMT-I, WEMT, N1THN        hoffmanxdelta.enet.dec.com:

>In article <3kl7vg$cpisaba.info.ucla.edu>, ronpisces.fusion.ucla.edu () writes:

>:

>:I've got a couple of disk controllers (Emulex QD21 and Dilog DQ686) in

>:a couple of MVII's that I want to junk.  I've got access to a MV3400 and

>:was wondering if the Q-bus backplanes are different on these systems.  I

>:realize that the mounting equipment is different (MVII's in BA23 vs the

>:MV3400 with a BA213), but I can tolerate some jury-rigging in this application.

>

>

>  ATTEMPT ANY AND ALL Q-BUS MODIFICATIONS AT YOUR OWN RISK -- CONTACT

>  YOUR HARDWARE SERVICE ORGANIZATION FOR FURTHER ASSISTANCE.

>

>  You may (will?) end up with RF emissions and/or RFI problems if the

>  enclosure is not properly RF-sealed.

>

>  First, if you are not familiar with working inside the Q-bus enclosure,

>  or if you are unfamiliar with the DMA grant continuity, or if you are

>  unwilling to make potentially permanent modifications to the card, or

>  if you are unwilling to place other cards at risk due to an incorrect

>  installation, or if you are unfamiliar with working with static-sensitive

>  electronic components, DO NOT ATTEMPT THIS.

>

>  Dual-width cards should install and operate in the upper half of the

>  slot in the BA2xx and BA4xx system.

>

>  If it is a quad-width card, what you are considering likely involves the

>  electrical modification of a Q22/Q22 card to operate in a Q22/CD slot. 

>  (In the BA23 and BA123, these Q22/CD slots are restricted to "memory" and

>  "processor" modules, and Quad-width boards can *not* be installed in these

>  slots.  The KA640 MicroVAX 3400 processor shipped in a BA2xx enclosure.)

>

>  Quad-width cards may/will cause you problems in the BA2xx or BA4xx series

>  Q22/CD enclosures -- you should be aware that a DMA grant continuity etch

>  on the lower half of the card is *not* permissible in a CD slot.  (All

>  BA2xx and BA4xx series enclosures are Q22/CD in all slots -- most (all?)

>  Q-bus cards not intended for use in the BA2xx or BA4xx series will have

>  this etch, and it will cause problems.)  If the DMA or Q-bus circuitry

>  is connected off the lower etch fingers, you will have real trouble here. 

>  If it is "just" the DMA grant continuity circuitry, some surgery on the

>  card etch may allow the card to operate in a Q22/CD slot.

>

>  I DO <**NOT**> RECOMMEND MAKING THESE MODIFICATIONS, NOR DO I RECOMMEND

>  INSTALLING MODULES IN AN ENCLOSURE THEY WERE NOT INTENDED TO RESIDE IN.

>  CONTACT YOUR HARDWARE SERVICE ORGANIZATION FOR FURTHER ASSISTANCE.



I'm certainly not going to disagree with the sentiments, but FWIW I believe 

it should be possible to use a quad height card in a Q22/CD backplane, 

provided some care is taken.



Because of the way that the CD connections work, I believe that the effect

of the DMA (and BR) grant continuity etches will depend entirely on the

adjacent cards. Putting a double height Q-bus grant card (or double height

module) in the AB slots either side of the quad height card should mean

that these grant etches are not connected to anything. 



I think. I may be wrong.





Mark Iline	systemmeng.ucl.ac.uk

Dept Mech Eng, University College, London. UK





From:	SMTP%"hoffmanxdelta.enet.dec.com" 22-MAR-1995 17:40:04.66

Subj:	Re: Sticking MV II cards into a MV3400





    Hello Mark Iline,



>Because of the way that the CD connections work, I believe that the effect

>of the DMA (and BR) grant continuity etches will depend entirely on the

>adjacent cards. Putting a double height Q-bus grant card (or double height

>module) in the AB slots either side of the quad height card should mean

>that these grant etches are not connected to anything. 



>I think. I may be wrong.



   Ignoring mounting and EMI/RFI, "dual" modules placed in the AB slots

   will work correctly in either BA23/BA123 or BA2xx/BA4xx.  The "quad"

   Q22-bus modules are the problematic ones.



   The CD (lower) section of the BA2xx and BA4xx is not a Q22-bus, it's

   part of the PMI CPU-memory interconnect bus.  Shorting the CD-PMI

   pins in the position that matches the CD-Q22-bus DMA grant continuity

   pins is not something I'd care to try.



   The last time I was swapping Q22-bus boards between the BA23/BA123 and

   the BA2xx/BA4xx series, I had to cut the DMA grant continuity etch on

   the BA23/BA123 "quad" modules to get them to work in the BA2xx/BA4xx.

   (The fellow that designed the particular module I was working with had

   specifically placed a zero-ohm resistor -- a jumper -- across these two

   pins to make cutting this easy.)



   I don't have the KA630/KA640/KA65x module pinouts handy to check what's

   in that pin position in tbe backplane.  If I can dig up a copy, I'll

   check to see what might happen when those two PMI pins are shorted.



   Steve



  ------------------------------ Opinionative -------------------------------

   Stephen Hoffman, NR EMT-I, WEMT, N1THN        hoffmanxdelta.enet.dec.com

        OpenVMS Engineering, Digital Equipment Corporation, Nashua NH



From:	DRKCLU::IVAX         "Mark Iline - Info-VAX account" 23-MAR-1995 12:42:36.99

Subj:	Re: Sticking MV II cards into a MV3400



Hi Steve.





>   Ignoring mounting and EMI/RFI, "dual" modules placed in the AB slots

>   will work correctly in either BA23/BA123 or BA2xx/BA4xx.  The "quad"

>   Q22-bus modules are the problematic ones.

>

>   The CD (lower) section of the BA2xx and BA4xx is not a Q22-bus, it's

>   part of the PMI CPU-memory interconnect bus.  Shorting the CD-PMI

>   pins in the position that matches the CD-Q22-bus DMA grant continuity

>   pins is not something I'd care to try.

>

>   The last time I was swapping Q22-bus boards between the BA23/BA123 and

>   the BA2xx/BA4xx series, I had to cut the DMA grant continuity etch on

>   the BA23/BA123 "quad" modules to get them to work in the BA2xx/BA4xx.

>   (The fellow that designed the particular module I was working with had

>   specifically placed a zero-ohm resistor -- a jumper -- across these two

>   pins to make cutting this easy.)

>

>   I don't have the KA630/KA640/KA65x module pinouts handy to check what's

>   in that pin position in tbe backplane.  If I can dig up a copy, I'll

>   check to see what might happen when those two PMI pins are shorted.

>



I've got a fair understanding of the problem. I'm not 100% sure, but my 

understanding is that the pins on the CD side of the backplane are simply 

connected such that the top contacts connect to the bottom contacts on the 

slot above, and so forth.



I think this originally came about for dual card controllers like the RLV11 

(the RLV211 was a single card, supporting 22 bits) (I think), so that the 

two cards didn't need an 'over the top' connector. The same mechanism 

allows LMI (uVAX II memory) to have its private memory bus (although it 

still needs a ribbon cable), and PMI (11/83 ?), in which the memory cards 

sit above the CPU card, whereas the Q-bus cards are below.



If I'm right about the CD wiring, as long as the CD slots either side of

the non-skunked quad height card are free, you should be ok, since the

grant tracks aren't connected to anything.





Mark



Mark Iline	systemmeng.ucl.ac.uk

Dept Mech Eng, University College, London. UK



From:	SMTP%"leichterlrw.com" 23-MAR-1995 14:08:03.12

To:	Info-VAXMvb.Saic.Com

CC:	

Subj:	Re: 100% CPU usage slows down other processes



	> [I wrote:]

	> Short of giving the real CPU hogs lower priorities, there isn't much

	> you can do on a V5.5-2 system.  V6.0 adds support for a class

	> scheduler, which allows you to assign processes to different

	> classes, each of which can only get some pre-defined fraction of the

	> available CPU time.  For example, you could assign processes that

	> are using a great deal of CPU time to class B, and all others to

	> class A, and the specify that class B is to be allows at most 70% of

	> the CPU.  All the CPU-bound processes together will share the 70%

	> give to class B, while 30% will remain available for everyone

	> else.  Again, however, this is new to V6.0.  (Actually, the

	> mechanism has been there for quite some time, but support and

	> documentation are new to V6.0.  I don't know if the newly-documented

	> $SCHED system call actually works the same way in V5.5.)



	I'm suprised this thread didn't continue with more discussion on the

	above statement. Can you tell me where this class scheduler is

	maintained from? What documentation should I be looking at to utilise

	this V6.0 feature?



The System Services manual, what else?  The basic operational model is that a

privileged process first uses $SCHED (CSH$_SET_QUANT function) to establish

a group of classes and assign class quanta to them.  As processes in different

classes run, VMS will deduct the time they use from their class's quantum.

When a class's quantum reaches 0, no processes in that class will be

scheduled until $SCHED is used to assign more time.



Then the privileged process asks VMS to tell it about all processes

(CSH$_READ_ALL) or only about processes that have not been assigned a

scheduler class (CSH$_READ_NEW), and if it wishes it assigns them

(CSH$_SET_CLASS).  Once it's done, the process can request that an AST be

delivered when new processes enter the system (CSH$_SET_ATTN_AST).  (It must

also arrange to use CSH$_SET_QUANT periodically to refresh the times allocated

to the various processes.  As a safety "dead-man" switch, VMS will disable

class scheduling if too long a time - normally 30 seconds, but this is

settable - goes by without the use of the CSH$_SET_QUANT function.)



I've seen an example of a simple class scheduler, but I'm not sure where.  It

may even be in the VMS V6.0 SYS$EXAMPLES; more likely, it appeared in a

Digital Systems Journal article within the last 6 months or so.  The code

examples from those articles are available on line somewhere, perhaps from

Hunter Goatley's site, but I'm not sure.



By the way, someone pointed out to me that the code for the scheduling facili-

ty was not shipped before V6.0.  (I seem to recall that it was being used

experimentally within DEC several versions earlier, but probably only on

specially-built development versions of VMS.)

							-- Jerry



From:	SMTP%"hoffmanxdelta.enet.dec.com" 23-MAR-1995 14:59:50.98

Subj:	Re: Sticking MV II cards into a MV3400





    Hello Mark Iline,



>>   The CD (lower) section of the BA2xx and BA4xx is not a Q22-bus, it's

>>   part of the PMI CPU-memory interconnect bus.  Shorting the CD-PMI

>>   pins in the position that matches the CD-Q22-bus DMA grant continuity

>>   pins is not something I'd care to try.

>>

>>   The last time I was swapping Q22-bus boards between the BA23/BA123 and

>>   the BA2xx/BA4xx series, I had to cut the DMA grant continuity etch on

>>   the BA23/BA123 "quad" modules to get them to work in the BA2xx/BA4xx.

>>   (The fellow that designed the particular module I was working with had

>>   specifically placed a zero-ohm resistor -- a jumper -- across these two

>>   pins to make cutting this easy.)

>>

>>   I don't have the KA630/KA640/KA65x module pinouts handy to check what's

>>   in that pin position in tbe backplane.  If I can dig up a copy, I'll

>>   check to see what might happen when those two PMI pins are shorted.



>I've got a fair understanding of the problem. I'm not 100% sure, but my 

>understanding is that the pins on the CD side of the backplane are simply 

>connected such that the top contacts connect to the bottom contacts on the 

>slot above, and so forth.



>I think this originally came about for dual card controllers like the RLV11 

>(the RLV211 was a single card, supporting 22 bits) (I think), so that the 

>two cards didn't need an 'over the top' connector. The same mechanism 

>allows LMI (uVAX II memory) to have its private memory bus (although it 

>still needs a ribbon cable), and PMI (11/83 ?), in which the memory cards 

>sit above the CPU card, whereas the Q-bus cards are below.



    Dual cards are, as I've mentioned, not a problem -- assuming they

    are installed in the AB portion of the BA2xx or BA4xx bus, and

    assuming EMI/RFI is handled.



>If I'm right about the CD wiring, as long as the CD slots either side of

>the non-skunked quad height card are free, you should be ok, since the

>grant tracks aren't connected to anything.



    Various members of the MicroVAX family used *both* the over-the-top

    ribbon cable *and* the CD portion of the backplane to communicate

    with the memory modules.  I *know* the KA650 puts out the main memory

    address on the CD pins on the backplane, and reads/writes the data via

    the over-the-top ribbon cable interconnect.  The memory control lines

    are also present on the CD pins.



    If you're right and the pin on the bottom of one card in the CD fingers

    is daisy-chained -- connected to the pin on the top of the next card

    in the bus, etc., then (with a gap between the modules) you're right,

    the configuration may work as long as no adjacent card(s) also use the

    CD.  I would not want to bet on this, and I would not want to leave

    this system for the next fellow to maintain -- it's too likely that

    a simple subsequent module addition or removal will have rather

    unforseen and puzzling consequences.  And if the card accesses the

    Q-signals bus via the CD pins as I could envision some (mis)designed

    modules doing, all bets are (obviously) off.



    In the particular configuration I were working with, one of the

    requirements was stuffing as many modules as we could into the box,

    and cutting the grant was thus necessary -- since the modules were

    backed up against the memory modules.



    Steve



  ------------------------------ Opinionative -------------------------------

   Stephen Hoffman, NR EMT-I, WEMT, N1THN        hoffmanxdelta.enet.dec.com

        OpenVMS Engineering, Digital Equipment Corporation, Nashua NH



From:	DRKCLU::IVAX         "Mark Iline - Info-VAX account" 23-MAR-1995 15:38:42.63

Subj:	Re: Sticking MV II cards into a MV3400



>>I think this originally came about for dual card controllers like the RLV11 

>>(the RLV211 was a single card, supporting 22 bits) (I think), so that the 

>>two cards didn't need an 'over the top' connector. The same mechanism 

>>allows LMI (uVAX II memory) to have its private memory bus (although it 

>>still needs a ribbon cable), and PMI (11/83 ?), in which the memory cards 

>>sit above the CPU card, whereas the Q-bus cards are below.

>

>    Dual cards are, as I've mentioned, not a problem -- assuming they

>    are installed in the AB portion of the BA2xx or BA4xx bus, and

>    assuming EMI/RFI is handled.



Ah, but I wasn't referring to dual *height* cards. The 'dual card' RLV11

controller was composed of 2 quad height cards that communicated over the

CD interconnect. 



>    If you're right and the pin on the bottom of one card in the CD fingers

>    is daisy-chained -- connected to the pin on the top of the next card

>    in the bus, etc., then (with a gap between the modules) you're right,

>    the configuration may work as long as no adjacent card(s) also use the

>    CD.  I would not want to bet on this, and I would not want to leave

>    this system for the next fellow to maintain -- it's too likely that

>    a simple subsequent module addition or removal will have rather

>    unforseen and puzzling consequences.  And if the card accesses the

>    Q-signals bus via the CD pins as I could envision some (mis)designed

>    modules doing, all bets are (obviously) off.



Fair point about maintainability.



I must admit, I'd doubt that any quad height cards that are at all recent

would access Q-bus lines via the CD slots. There's no point, and Q/CD

backplanes were common around the time of the (pre-BA23) 11/23 (in fact

probably with DEC supplied 11/03s, precisely because of the RLV11. As

you've observed, modules were designed to work either in the 'serpentine'

Q/Q backplanes, or the 'straight down' Q/CD backplanes by having only

grants on the CD slots, and jumpers to disconnect these.



>    In the particular configuration I were working with, one of the

>    requirements was stuffing as many modules as we could into the box,

>    and cutting the grant was thus necessary -- since the modules were

>    backed up against the memory modules.



Surely not moving the graphics card on a VSII/RC (5 slot VSII) into a Q/CD 

slot to free up another double height Q-bus slot ;-) ? Naughty people like 

us took the araldite/epoxy out of the other 3 slots.





Mark