[N8VEM: 17239] ECB 12-slot Extended Backplanes arrived

Discussion:

John Coffman

2014-01-28 19:55:38 UTC

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To All, 
 
The shipment of the 12-slot Extended Backplanes (for the Siemens
505-6508 case) arrived yesterday (1/27).  I've been scrambling to
get the lot shipped out to those of you who ordered them.  They
should all ship by today. 
 
Good News:  the fit in the 6508 case is excellent.  The alignment
notch holds the connectors in the proper position for easy card
insertion, and the two mounting screw holes line up perfectly. 
 
There are two possible clearance issues. 
    1.  The fit of the P2 (IBM PC 4-pin) power connector is tight. 
Trim the pin 1 side as needed. 
    2.  Judging by the silkscreen outline, the coin cell battery
holder may be tight depending upon which socket is used. 
 
Now I am waiting for a dozen DIN 41612 connectors to arrive. 
 
--John 
 
 
 
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Andrew Bingham

2014-01-28 20:16:26 UTC

Permalink

John,

Great news! I'm looking forward to starting my ECB build. I've been
struggling with a vintage Vector MZ that is going to likely require
extensive refurb on one of the floppy drives, so getting a new build where
I have known good components going will be satisfying.

Andrew

Post by John Coffman
To All,
The shipment of the 12-slot Extended Backplanes (for the Siemens 505-6508
case) arrived yesterday (1/27). I've been scrambling to get the lot
shipped out to those of you who ordered them. They should all ship by
today.
Good News: the fit in the 6508 case is excellent. The alignment notch
holds the connectors in the proper position for easy card insertion, and
the two mounting screw holes line up perfectly.
There are two possible clearance issues.
1. The fit of the P2 (IBM PC 4-pin) power connector is tight. Trim
the pin 1 side as needed.
2. Judging by the silkscreen outline, the coin cell battery holder
may be tight depending upon which socket is used.
Now I am waiting for a dozen DIN 41612 connectors to arrive.
--John

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Fabio Battaglia

2014-01-28 20:25:38 UTC

Permalink

Great! I received my two chassis just today!
Can't wait to build my backplanes.

Vince Mulhollon

2014-01-28 20:41:38 UTC

Permalink

Post by John Coffman
Now I am waiting for a dozen DIN 41612 connectors to arrive.

John Coffman

2014-01-29 01:44:55 UTC

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Between Digikey and Jameco, Jameco is slightly lower.  You get a
price break both places for qty. 10 or more.  I used the AMP
535090-5 part.  The  AMP 535090-4 part differs in the plating on the
connector pins. 
 
--John 
 
 
 
On 01/28/2014 12:41 PM, Vince Mulhollon wrote:
<blockquote
cite="mid:8beb9965-dd73-4ff8-a131-b0edee396f88-/***@public.gmane.org"
type="cite">
<div dir="ltr">On Tuesday, January 28, 2014 1:55:38 PM UTC-6, John
Coffman wrote:
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt
0.8ex; border-left: 1px solid rgb(204, 204, 204);
padding-left: 1ex;">
<div bgcolor="#ffffff" text="#000000"> Now I am waiting for a
dozen DIN 41612 connectors to arrive. 
</div>
</blockquote>
<div> 
Speaking of a dozen 41612, has anyone begun research on
cheapest / best source commercial source of connectors? 
 
Don't need long solder tail for this, its a 1/16th inch thick
board, I believe, so wouldn't necessarily be the same
connectors as the smaller, thick board. 
</div>
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Tom Lafleur

2014-01-29 13:01:37 UTC

Permalink

Avnet express sell 535090-5 for $3.50 each at qty of 10 or more. -4 are $3.70

Digikey is $4.68 each, qty 10, Jamco is $4.29

i~~ _/) ~~~~ _/) ~~~~ _/) ~~~~ _/) ~~i

Tom Lafleur
(858) 759-9692

Between Digikey and Jameco, Jameco is slightly lower. You get a price break both places for qty. 10 or more. I used the AMP 535090-5 part. The AMP 535090-4 part differs in the plating on the connector pins.
--John

Post by John Coffman
Now I am waiting for a dozen DIN 41612 connectors to arrive.

Speaking of a dozen 41612, has anyone begun research on cheapest / best source commercial source of connectors?
Don't need long solder tail for this, its a 1/16th inch thick board, I believe, so wouldn't necessarily be the same connectors as the smaller, thick board.
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John Coffman

2014-01-29 15:05:56 UTC

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I just posted 2 pix of the backplane in the 505-6508 chassis.  Note
use of the butchered IBM peripheral extension cord as the quick
disconnect power source. 
 
<a
href="http://n8vem-sbc.pbworks.com/w/file/73908647/ExtBkPln-6508-chassis-IMG_0424.jpg" style="padding: 7px 8px; background-color: #F6FEFF; border-left: 1px solid #8FF1FF; margin: 10px 0px; display: inline-block; color: #3B5053; font-size: 13px; ">Loading Image...

</a> 
 
<a
href="http://n8vem-sbc.pbworks.com/w/file/73908653/ExtBkPln-6508-chassis-IMG_0425.jpg" style="padding: 7px 8px; background-color: #F6FEFF; border-left: 1px solid #8FF1FF; margin: 10px 0px; display: inline-block; color: #3B5053; font-size: 13px; ">Loading Image...

</a> 
 
BTW:  the vertical board is a retired, cannibalized, SBC v1. 
 
--John 
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Edward Snider

2014-01-29 17:15:13 UTC

Permalink

Wow, that looks really nice.

I just posted 2 pix of the backplane in the 505-6508 chassis. Note use
of the butchered IBM peripheral extension cord as the quick disconnect
power source.
Loading Image...

Loading Image...

BTW: the vertical board is a retired, cannibalized, SBC v1.
--John

Vince Mulhollon

2014-01-29 17:39:42 UTC

Permalink

Comments on the mechanical stability of 3U installed in "top" of the
chassis? Or are there card hook / retainer already in the works? Or could
I build some kind of retainer? Hoping cards can't fall out...

I'm beginning to think of my carpentry project to hold the chassis, this
early in the design it would be no big deal to go "drawer" and "cards
upright" such that gravity holds the cards in place, but if I'm missing
something about card retention then I could safely mount the chassis cards
"forward" behind doors instead of a drawer.

Or I could go "door" and "forward" mounted chassis and put some kind of
finely made blocking such that slots 6-12 are 3U only, or whatever. Or
play games with precision cut sheets of lexan, either on the milling
machine or the table saw, to convert a standard 3U card into a sorta 6U
card.

My carpentry ideas are beginning to form on something the looks like the
love child of a secretary desk and an antique Victrola. I want to do
something other than the fairly obvious filing cabinet idea. Not that
there's anything wrong with that, I just want to build something else.

John Coffman

2014-01-30 01:06:54 UTC

Permalink

Vince,

I would just invert the rack so that the cards are on the bottom. Then
gravity is holding them; i.e., is working for you. Vertical mounting,
as I have always done it with the 8- and 6- slot backplanes, is quite
stable (as photographed): the reason being that the DIN connector is
quite stiff in holding on to 96 pins.

A "door" on the front might not be practical, unless it has holes &
slots in it to access card edge connectors on boards like: CVDU, Dual
IDE, Dual SD, Mark IV, &c. I think the open space opposite the rack of
cards will accumulate a few cables, and, perhaps, a floppy or hard disk.

--John

Post by Vince Mulhollon
Comments on the mechanical stability of 3U installed in "top" of the
chassis? Or are there card hook / retainer already in the works? Or
could I build some kind of retainer? Hoping cards can't fall out...
I'm beginning to think of my carpentry project to hold the chassis,
this early in the design it would be no big deal to go "drawer" and
"cards upright" such that gravity holds the cards in place, but if I'm
missing something about card retention then I could safely mount the
chassis cards "forward" behind doors instead of a drawer.
Or I could go "door" and "forward" mounted chassis and put some kind
of finely made blocking such that slots 6-12 are 3U only, or
whatever. Or play games with precision cut sheets of lexan, either on
the milling machine or the table saw, to convert a standard 3U card
into a sorta 6U card.
My carpentry ideas are beginning to form on something the looks like
the love child of a secretary desk and an antique Victrola. I want to
do something other than the fairly obvious filing cabinet idea. Not
that there's anything wrong with that, I just want to build something
else.
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G. Beat

2014-01-29 23:56:51 UTC

Permalink

John,
Correct e-mail for PayPal ?

g. beat

John Coffman

2014-01-30 01:17:09 UTC

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Gregory, 
 
If you are referring to the the 12-slot backplane referenced in the
Subject line, I regret to say that all of the boards in this
production run are sold.  I would need to know that there is
sufficient interest in about ten more boards to re-order them. 
 
I will accumulate inquiries for now as an indicator of the demand
for these items. 
 
--John 
 
 
 
 
On 01/29/2014 03:56 PM, G. Beat wrote:
<blockquote
cite="mid:0fec1ef3-d71b-4195-99d4-492ff712c627-/***@public.gmane.org"
type="cite">
<pre wrap="">John,
Correct e-mail for PayPal ?

g. beat

</pre>
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John Coffman

2014-01-29 02:29:43 UTC

Permalink

Regarding clearance issue 1, below:

The silkscreen outline for the P2 connector is deceiving. It merely
indicates orientation, not the size of the connector.

1. below should be revised to read:
"If using the 6508 chassis, DO NOT SOLDER the P2 connector. Instead use
the wiring option suggested in the "Wiring Instructions" on the Wiki."

--John

John Coffman

2014-02-01 01:47:32 UTC

Permalink

Regarding clearance issue 2, way below:

The Kicad Library strikes again. The footprint of the CR2032 batter holder
bears no relation to the actual diameter of said coin cell battery.

2. below should be revised to read:
"If using the 505-6508 Siemens card cage, the BAT1 battery holder will
not fit. It fits fine if you will be using the backplane stand-alone."

(I just posted an update to the parts list on the Wiki to reflect this
clearance issue.)

--John

Post by John Coffman
The silkscreen outline for the P2 connector is deceiving. It merely
indicates orientation, not the size of the connector.
"If using the 6508 chassis, DO NOT SOLDER the P2 connector. Instead
use the wiring option suggested in the "Wiring Instructions" on the Wiki."
--John

yoda

2014-02-01 04:33:23 UTC

Permalink

John,

Got the boards - they are really nice and fit perfectly. I was just
thinking of a couple of things. Maybe on V2 you might consider dropping
one slot and move battery clip etc to the end of the board. I would think
you would want to drop the 7805 so no one would be tempted to power this as
after a board or 2 you will exceed the current rating. Question - with
this number of slots will any termination be required like on S100 bus
motherboards? Another reason you might need space for active termination.

John Coffman

2014-02-02 04:27:30 UTC

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The question of termination arose a couple of years ago.  I have a 7
slot S-100 with termination networks, and I have trouble at 6Mhz. 
The system only works with the boards plugged in in a certain order. 
 
The 6 and 8 slot ECB backplanes seem to have little noise problems. 
The SBC-188 will run at 16Mhz with a 4MEM board to fill out the
memory, and as Expanded Memory.  That was the design goal for the
board, so I'm pretty happy with the result. 
 
Apparently, the earlier 12-slot backplane had no obvious noise
problems at SBCv1/v2 frequencies.  Of course, I/O runs at 1 wait
state.  We will have to see if this board is as noise immune. 
 
Yes, I think the 5v regulator should go.  No way will it power a
load of boards. 
 
Making an appropriate (meaning, full diameter) footprint of the
coin-cell holder, I think it can be squeezed in where the LEDs now
sit.  I do note that the outline of the DIN 41612 connectors is
accurate, although the mounting holes are in the wrong position by a
few mils. 
 
--John 
 
 
 
 
On 01/31/2014 08:33 PM, yoda wrote:
<blockquote
cite="mid:60ed33a8-0915-4c60-a554-9def08332064-/***@public.gmane.org"
type="cite">
<div dir="ltr">John,
<div> 
</div>
<div>Got the boards - they are really nice and fit perfectly.  I
was just thinking of a couple of things.  Maybe on V2 you
might consider dropping one slot and move battery clip etc to
the end of the board.  I would think you would want to drop
the 7805 so no one would be tempted to power this as after a
board or 2 you will exceed the current rating.   Question -
with this number of slots will any termination be required
like on S100 bus motherboards?  Another reason you might need
space for active termination.</div>
</div>
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Wayne Warthen

2014-02-03 05:51:11 UTC

Permalink

I just did a "test fit" of the stuff I am trying to put in the Siemens
cage. Picture attached. Coming together very nicely.

Power supply will be moved to the top and properly bolted in place. The
floppy drives will also be properly attached on short standoffs.

Sitting on top, I have a DSKY and next to it is my Zeta (for no particular
reason other than there was room for it).

Oh, you will see that I removed the card guide from the side that is not
used. It is easy to do without destroying it by prying out the bottom
first. I actually think that with some ingenuity it may be possible to
relocate the second card guide next to the cards such that the cards have
guides on both sides.

Thanks for this great backplane John!

--Wayne

Paul Birkel

2014-02-03 06:33:33 UTC

Permalink

1. Given the positioning of the power supply cord I'd think that you'd want
to move the supply to the bottom and (instead) the floppy drives to the top?

2. What is that board attached to the side of the power supply? I can't
quite visually-disentangle your wiring ...

THX! Is that your preferred operating orientation (in which case another
reason to move the power supply to the bottom ...)?

Post by Wayne Warthen
I just did a "test fit" of the stuff I am trying to put in the Siemens
cage. Picture attached. Coming together very nicely.
Power supply will be moved to the top and properly bolted in place. The
floppy drives will also be properly attached on short standoffs.
Sitting on top, I have a DSKY and next to it is my Zeta (for no particular
reason other than there was room for it).
Oh, you will see that I removed the card guide from the side that is not
used. It is easy to do without destroying it by prying out the bottom
first. I actually think that with some ingenuity it may be possible to
relocate the second card guide next to the cards such that the cards have
guides on both sides.
Thanks for this great backplane John!
--Wayne
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Wayne Warthen

2014-02-03 07:41:32 UTC

Permalink

I would definitely prefer that the power supply go on the bottom, but I can
see no easy way to attach the floppy drives to the top of the cage. Ideas?

The little board you noticed is a small USB-to-GPIO thingy that I use to
control the power on/off of the power supply remotely from my host
computer. I also use a GPIO pin to pulse /RESET as needed. This allows me
to completely control the entire setup from the host PC which is running
the terminal emulator.

Yes, that is my preferred orientation. I considered having the ECB boards
on top, but kind of disliked having them "hang" even though they seem
pretty secure. Having the ECB boards on top would fix the power supply
issue because both the power supply and floppy drives would mount nicely on
the bottom.

--Wayne

Post by Paul Birkel
1. Given the positioning of the power supply cord I'd think that you'd
want to move the supply to the bottom and (instead) the floppy drives to
the top?
2. What is that board attached to the side of the power supply? I can't
quite visually-disentangle your wiring ...
THX! Is that your preferred operating orientation (in which case another
reason to move the power supply to the bottom ...)?

Post by Wayne Warthen
I just did a "test fit" of the stuff I am trying to put in the Siemens
cage. Picture attached. Coming together very nicely.
Power supply will be moved to the top and properly bolted in place. The
floppy drives will also be properly attached on short standoffs.
Sitting on top, I have a DSKY and next to it is my Zeta (for no
particular reason other than there was room for it).
Oh, you will see that I removed the card guide from the side that is not
used. It is easy to do without destroying it by prying out the bottom
first. I actually think that with some ingenuity it may be possible to
relocate the second card guide next to the cards such that the cards have
guides on both sides.
Thanks for this great backplane John!
--Wayne
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Paul Birkel

2014-02-03 08:12:25 UTC

Permalink

Attach them upside-down :->? I gather that there's insufficient space to
attach to the "side" grill?

Alternatively I'd get some aluminum bar-stock, drill/tap the ends, and then
remount the second card-rails in the middle, which would give you some more
interior-options to work with while ensuring good card-support.

In my case I'm thinking that I want to preserve at least some of the 6U
space for current-and-future boards, but perhaps less than the full set of
slots ... leaving some interior space for floppy drives. But the power
supply would then end up being outboard .. perhaps mounted to the
cage-exterior.

Would love to hear more specifics regarding your "USB-to-GPIO thingy"; your
approach sounds generally useful in a variety of scenarios!

-----
paul

Post by Wayne Warthen
I would definitely prefer that the power supply go on the bottom, but I
can see no easy way to attach the floppy drives to the top of the cage.
Ideas?
The little board you noticed is a small USB-to-GPIO thingy that I use to
control the power on/off of the power supply remotely from my host
computer. I also use a GPIO pin to pulse /RESET as needed. This allows me
to completely control the entire setup from the host PC which is running
the terminal emulator.
Yes, that is my preferred orientation. I considered having the ECB boards
on top, but kind of disliked having them "hang" even though they seem
pretty secure. Having the ECB boards on top would fix the power supply
issue because both the power supply and floppy drives would mount nicely on
the bottom.
--Wayne

Post by Wayne Warthen
I just did a "test fit" of the stuff I am trying to put in the Siemens
cage. Picture attached. Coming together very nicely.
Power supply will be moved to the top and properly bolted in place. The
floppy drives will also be properly attached on short standoffs.
Sitting on top, I have a DSKY and next to it is my Zeta (for no
particular reason other than there was room for it).
Oh, you will see that I removed the card guide from the side that is not
used. It is easy to do without destroying it by prying out the bottom
first. I actually think that with some ingenuity it may be possible to
relocate the second card guide next to the cards such that the cards have
guides on both sides.
Thanks for this great backplane John!
--Wayne
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Wayne Warthen

2014-02-03 15:31:44 UTC

Permalink

I'm going to give the floppy mounting issue some more thought. If I can
just find a very simple metal cage for a pair of 3.5" floppy drives, I
would be all set. Definitely prefer the idea of top mounting the floppy
drives.

So, the USB-to-GPIO thingy is a "SUB-20" from DIMAX. Web page is
http://www.xdimax.com/sub20/sub20.html. It works well, but is too
expensive for what it is. I think this device from Numato Lab would be
just as good: http://numato.com/8-channel-usb-gpio-module. It is much
cheaper. I power the SUB-20 with the standby current from the power
supply and connect the USB port to my host machine which also runs the
terminal emulation software. I am a bit anal about wanting to control
everything electronically. It also allows me to do quite a bit of software
development "from my couch" with a laptop.

I have had the idea for some time to play with a new backplane variant that
would incorporate some of this. The idea was to use one of the
USB-to-serial chips that include a few GPIO pins. That could be added to a
backplane to provide both a USB-to-serial interface along with the ability
to control power supply on/off and bus reset. The 20-pin connector of the
power supply would attach directly to the backplane in this configuration.
One of these days, I may try to experiment with that.

--Wayne

Post by Paul Birkel
Attach them upside-down :->? I gather that there's insufficient space to
attach to the "side" grill?
Alternatively I'd get some aluminum bar-stock, drill/tap the ends, and
then remount the second card-rails in the middle, which would give you some
more interior-options to work with while ensuring good card-support.
In my case I'm thinking that I want to preserve at least some of the 6U
space for current-and-future boards, but perhaps less than the full set of
slots ... leaving some interior space for floppy drives. But the power
supply would then end up being outboard .. perhaps mounted to the
cage-exterior.
Would love to hear more specifics regarding your "USB-to-GPIO thingy";
your approach sounds generally useful in a variety of scenarios!
-----
paul

Post by Wayne Warthen
I would definitely prefer that the power supply go on the bottom, but I
can see no easy way to attach the floppy drives to the top of the cage.
Ideas?
The little board you noticed is a small USB-to-GPIO thingy that I use to
control the power on/off of the power supply remotely from my host
computer. I also use a GPIO pin to pulse /RESET as needed. This allows me
to completely control the entire setup from the host PC which is running
the terminal emulator.
Yes, that is my preferred orientation. I considered having the ECB
boards on top, but kind of disliked having them "hang" even though they
seem pretty secure. Having the ECB boards on top would fix the power
supply issue because both the power supply and floppy drives would mount
nicely on the bottom.
--Wayne

Post by Paul Birkel
1. Given the positioning of the power supply cord I'd think that you'd
want to move the supply to the bottom and (instead) the floppy drives to
the top?
2. What is that board attached to the side of the power supply? I can't
quite visually-disentangle your wiring ...
THX! Is that your preferred operating orientation (in which case
another reason to move the power supply to the bottom ...)?

Post by Wayne Warthen
I just did a "test fit" of the stuff I am trying to put in the Siemens
cage. Picture attached. Coming together very nicely.
Power supply will be moved to the top and properly bolted in place.
The floppy drives will also be properly attached on short standoffs.
Sitting on top, I have a DSKY and next to it is my Zeta (for no
particular reason other than there was room for it).
Oh, you will see that I removed the card guide from the side that is
not used. It is easy to do without destroying it by prying out the bottom
first. I actually think that with some ingenuity it may be possible to
relocate the second card guide next to the cards such that the cards have
guides on both sides.
Thanks for this great backplane John!
--Wayne
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Vince Mulhollon

2014-02-03 16:40:19 UTC

Permalink

Post by Wayne Warthen
I'm going to give the floppy mounting issue some more thought.

I have two chassis sitting on the basement floor, as I think about this.
You're further along than I am.

One thing I can't get out of my head is there must be some way to take
advantage of 3U ECB dimensions of 100mm x 160mm vs the width of a 3.5 inch
floppy is only 89 mm. Also the ECB provides 5V and most 3.5 floppies don't
need or use 12V. Something like a 6U prototyping blank PCB could easily
and attractively mount and power two floppies. Or I have the equipment to
mill a 1/16th or so thick sheet of aluminum to make a psuedo-card 6U sized
that would hold some drives inside the card cage. Will need angle barstock
to stiffen the card as the thin aluminum will be floppy (groan at that pun).

Theoretically, if a 6U diskIOv4 someday appears, assuming the worldwide
supply of FDC9266 controllers holds out, that card could direct mount and
power floppy drives much like the S100 IDE card holds CF cards. That would
look nice.

Another idea I have rattling around is a nice spacer (key word, nice) to
push the 3U cards up against their slots while leaving the space for some
6U cards.

I have a trick for mounting 3.5 inch drives you may be interested in, which
involves mounting a 5 inch to 3.5 inch adapter where you want and then
mount the 3.5 inch drive in the adapter. Given the design of typical 3.5
to 5 adapters, mounting an adapter is usually a lot easier than getting the
hole positions and locations for a direct mount 3.5 correct. Also most 3.5
disks can be mounted right side up or upside down in most 3.5 to 5
adapters. My P112 case requires some work before its done, but this is the
basic design, a U with adapters hanging underneath the U side by side and
drives mounted in the adapters. I cannot finish wood indoors, or outdoors
when its -5F, so the P112 project is stalled until wx improves.