On Mon, Apr 8, 2024 at 2:25=E2=80=AFPM <<= a href=3D"mailto:craig@sbc-85.com">craig@sbc-85.com> wrote:

Hi Scott. I do not and have been looking for one f= or my iPDS for quite some time. If you come across one I would like go= od photos so I can make a reproduction.

Regards
craig<= /u>
&= nbsp;
From: Scott Baker <smbaker@gmail.com>
Sent: Monday, April 8, 2024 2:2= 2 PM
To: SBC-85 <craig@sbc-85.com>
Subject: Re: [Tindie Community] [= PM] Order status

Hey Craig, I know you've colle= cted a lot of stuff, including SBX251 modules. Long-shot, but I was wonderin= g if you had come across a "multimodule adapter" for an iPDS. Looks like the= picture below. Basically just a carrier board with some logic. I've been tr= ying to find one...
&nbs= p;
Scott
<= p class=3D"MsoNormal">
<image001.jpg>

O= n Sat, Jul 8, 2023 at 9:34=E2=80= =AFAM Scott Baker <smbaker@gmail.com> wrote:
You might have already seen it, but my s= econd bubble video is now up -- https://www.youtube.com/watch?v=3DsNuio= 7UfHlc
=
Scott

= On Thu, Jun 29, 2023 at 4:27=E2= =80=AFPM Scott Baker <smbaker@gmail.com> wrote:
The last 1% was conquered. I was able t= o read and write the double-bubble in Heathkit HDOS without issue. I will pr= obably do a video, but to the average person (i.e. everyone but you and I!) t= he experience won't look much different than the single-bubble board. The CP= U requirements are challenging as the bubble scales -- I wish I had designed= my board so that it supported interrupts. If I do a respin some day...

=
The secret to the double-bubble is what I mentioned a= bout 1 message upthread, namely the need to initialize with the NFC set= to 0001 (as if you're initializing a single-bubble system) and the Group Se= lect set to the last bubble. If you don't do that, all sorts of things will g= o comically wrong (like the two memories becoming disassociated after the ne= xt reset).
<= u>
Scott

On Tue, Jun 27, 2023 at 9:25=E2=80=AFPM SBC-85 <craig@sbc-85.com> wrote:
I remember this now that you sa= id it, but would have been hard pressed to recall it at Will.<= /p>

How did the last 1% go? Looking forward to a follow up vi= deo on the two bubble system.
Did you have to reseed and bubbles using my reseed module?
Regards
<= p class=3D"MsoNormal">Craig

On Jun 18, 2023,= at 8:40 PM, Scott Baker <smbaker@gmail.com> wrote:
=EF=BB=BF
It took a while, but I think I close= d on the remaining 1%.
&= nbsp;
Here's the only real trick= in the manual (in the BPK-72 manual, but not in the 7220 datasheet, not as f= ar as I could tell):
<= /u>
"The BMC executes the I= nitialize command by first interrogating the bubble system
to determine h= ow many FSAs are present, then reading and decoding the bootloop
from eac= h MBM and storing the results in the corresponding FSA=E2=80=99s bootloopregister. The NFC bits in the BLR MSB must be set to 0001 before issuing= the
Initialize command. The MBM GROUP SELECT bits (in the AR) must selec= t the
last MBM in the system."

If you= mess this up, then various bad things can happen. For example, I was initia= lizing with BLR_MSB set properly, but had the BAR selecting the wrong MBM. T= his caused everything to appear to work fine until I rebooted, then I would g= et a plethora of errors after the next initialization. Perhaps it was becaus= e the bootloop for the second memory wasn't getting loaded. Anyhow, I fixed&= nbsp;the bug and it's working now.

The= CPU requirements also turned out to scale steeper than expected. Whereas my= 2MHz Z80 can handle a single bubble, my 4MHz Z80 cannot. I had to step the&= nbsp;Z80 up to 8MHz to get it to work. I'm hoping a 5MHz 8085 will also work= .

Scott

On= Sun, Jun 18, 2023 at 8:18=E2=80= =AFPM SBC-85 <craig@sbc-85.com> wrote:
=
Hi Scott,
No, I have not built a multi-bubble. So if there are= any hidden tricks I am very interested. You have no doubt seen intels= design for multiple bubbles.
I may make a STD bus bubble board and would have room for a double on t= hat.
=
Regards
Craig

On Jun 18, 2023, a= t 4:39 PM, Scott Baker <smbaker@gmail.com> wrote:
<= blockquote style=3D"margin-top:5pt;margin-bottom:5pt">
=EF=BB=BF<= u>
Behold, the mighty double-bubble!

=
Do you have any experience with multiple-bubble desig= ns? Getting this working gave me a bit of grief, and I think I'm only about 9= 9% there with 1% left to figure out.

Scott<= u>

=
On Tue, Jun 6, 2023 at 10:44=E2=80=AFPM Scott Baker <smbaker@gmail.com> wrote:=
Gla= d you found your way there -- I was just about to send you a pointer to the v= ideo.

<= /div>
I've updated the link to your site. Thanks a= lot for all the help!

Scott<= /p>

On Tue, Jun 6, 2023 at 6:22=E2=80=AFPM <craig@sbc-85.com> wrote:
Hi Scott=

I s= aw the H8 bubble project on your website and the video. Great work and= thanks for the shout out.
=
could you change the sbc-85.com blog post link on your website= to this updated version--
=
https:/= /bitsofthegoldenage.org/bubble-memory-makes-a-comeback-for-me-anyway/=

thanks=

cr= aig

From:= smbaker@gmail.co= m <smbaker@gma= il.com>
Sent: Saturday, June 3, 2023 1:12 PM
To:= SBC-85 <craig@sbc-= 85.com>
Subject: Re: [Tindie Community] [PM] Order status

<= p class=3D"MsoNormal">I=E2=80=99m off at a ham radio thing today myself, but= I did set my bubble memory video to premier this morning on YouTube. I=E2=80= =99ll see if I can dig up the link later. Basically I built a bubble memory b= oard for the Heathkit h8 and wrote a storage driver for it (heavily leveragi= ng your code!)
=
Scott=
Sent from my iPhone<= /u>

On Jun 3, 2023, at 11:55 AM,= SBC-85 <craig@sbc-= 85.com> wrote:
=EF=BB=BF
Hi Scott,
Thanks, I will send these out when I am back in town Monday.=

<= div>
Any info on your bubble projects that you want to= share?
<= /u>
Regards
Craig

On Jun 1, 2023, at 5:03 PM, Scott Baker <smbaker@gmail.com> wrote:=
=EF=BB=BF
FYI, order= ed another couple BPK-70s and another couple controller ICs. Got at least a c= ouple more good bubble memory ideas left, I think. :)
=

I did send a request for the 86 date code ones if possible.

<= p class=3D"MsoNormal">Scott

On Wed, May 24,= 2023 at 8:25=E2=80=AFPM= SBC-85 <craig@sbc-= 85.com> wrote:
Yes, exactly. Page size is 64 bytes when ECC is enabled an= d if ECC is disabled then those 3 bytes become data.
= ;
On May 24, 2023, at 3:28 PM, Scott B= aker <smbaker@gmai= l.com> wrote:
=EF=BB=BF
Craig, something that confuses the heck out of me is the 6= 8-byte data transfers instead of 64-byte. Reading the datasheet, it jus= t isn't jumping out at me why this is so, other than maybe it has something t= o do with bits reserved for ECC.

Everything I rea= d in the datasheets suggest to me that the controller implements 2048 pages o= f 64 bytes each, yet the code clearly transfers 68 bytes at a time.

68-byte pages seem really inconvenient to deal with= .

Since you've implemented this already, yo= u probably know what I'm misunderstanding.

= Scott

On Tue, May 23, 2023 at 11:28=E2=80=AFAM SBC-85 <craig@sbc-85.com> wrote:<= u>
Congratula= tions!

The bubble chips are thankful they a= re being utilized rather than cast into a paperweight for some =E2=80=9Ccoll= ector=E2=80=9D

On= May 22, 2023, at 10:17 PM, Scott Baker <smbaker@gmail.com> wrote:
=
=EF=BB=BF=
I think I can claim vic= tory!

<= /div>
BUBBLE TOOL
404040
>T
TESTING P= AGE --07FF
>
=
Scott
<= /div>

On Mon, May 22, 2023 at 9:37=E2=80=AFAM SBC-85 <craig@sbc-85.com> wrote:
<= blockquote style=3D"border-top:none;border-right:none;border-bottom:none;bor= der-left:1pt solid rgb(204,204,204);padding:0in 0in 0in 6pt;margin:5pt 0in 5= pt 4.8pt">
=EF=BB=BF
Despite my best efforts, I have not been able to raise interest in multi= bus. Everyone is enamored with s100 for some reason. So I would imagin= e that there are not a lot of people in the 251. I frequently watch it= ems for a year or more until the price drops. Personally, I think the v= intage computer prices is back on its way down. I frequently see things sitt= ing on eBay for months that are priced incredibly reasonable or even underpr= iced. I know none of that helps when shopping for something very speci= fic.
=
The Z coil is isolated, so yes, leavin= g one lead floating is sufficient. I reread that part of the manual an= d am sure I knew much more about the bubbles than I do now, so I trust earli= er me. To be honest, most of the documentation and videos I do are to r= emind future me of details I have forgotten.

To answer your question about the 7220 testing, current me wasn=E2=80= =99t even sure what test software that former me was talking about in the ma= nual, so I obviously need to add more specifics about the test routines to t= he users manual. Maybe I have good information in the header of those f= iles, I haven=E2=80=99t looked yet.

= Now that I have refreshed my memory about bubble test , I remember spending h= ours getting that all to work and testing, but I do not specifically remembe= r why I had the abort command in that specific spot. I dont see any r= equirement for the abort unless something was hanging that needed to be clea= ned up. I would say that if you are reliably getting your buffer data b= ack, you can move on and see how the tests with the formatter go. It w= ill be a week or so before I will get a chance test this again. In the mean t= ime, keep me posted.
&nbs= p;
You have seen this?&nb= sp;
<883248167803527980= 5.jpg>
An OS and SW Tools For The SBC-85<= /a>
<= span style=3D"color:rgb(162,162,169);text-decoration:none">hackaday.io

On May 21, 2023, at 11:31 PM, Scott Baker <smbaker@gmail.com> wrote:<= u>
=EF=BB=BF
Part of me wants to buy the silly SBC-215. But part of me is more reason= able and thinks I should wait for it to sit a few months and see if the sell= er comes to his senses...

Just to clarify, for y= our schematic, for the 7110AZ it's sufficient to only leave #13 discon= nected (pin 6 is connected to +12V via 47ohm resistor). Want to make su= re before I plug in my bubble module tomorrow... :)

Also a few questions about the 7220 controller test. I'm testing with onl= y the 7220. No 7242 yet. If I execute the following instructions from the us= er manual.
<= u>
1. Fill the FIFO using F<= u>
2. Issue an abort using #9
3. Read the FIFO using G
4. Dump the input buffer

=
Then I end up reading back 0xFF from the FIFO. S= hould step 2 (issue an abort) be omitted? If I skip that step, then I'm able= to read back the fill message as expected.

Scott

<= p class=3D"MsoNormal">On Sun, May 21, 2023 at 9:18=E2=80=AFPM SBC-85 <craig@sbc-85.com> wrote:
=
6 and 13 are the Z axis. I= t looks like they are left unconnected on this board.

On May 21, 2023, at 7:25 PM, Scott Bake= r <smbaker@gmail.c= om> wrote:
=EF=BB=BF
It's this one -- https://www.ebay.com/itm/144006137223 -- l= ooks like there is a PBA on the front side.

Scott<= u>

=
On Sun, May 21, 2023 at 6:37=E2=80=AFPM SBC-85 <craig@sbc-85.com> wrote:=
There are three= versions and all require different pinout. The original 7110 leadless that g= oes in a carrier, the 7110A that is the pinned version, and the 7110AZ that i= s also pinned but has the Z-axis bulk erase so the pinout is slightly modifi= ed.

I would like to see if the Z vers= ion of the 251 utilizes the bulk erase or if unused.
=

The 251 had many revisions and at least two pcb numbers. Do y= ou know what the PCA and PCB numbers are on the board you are looking a= t? Maybe ask seller for additional photos with the board numbers

<= p class=3D"MsoNormal">Regards
Craig.

On Ma= y 21, 2023, at 6:23 PM, Scott Baker <smbaker@gmail.com> wrote:
=EF=BB=BF
Thanks Craig, I don't thi= nk this seller is going to budge. They're some large outfit selling what loo= ked primarily like industrial stuff. I got back a "thanks for the inquiry bu= t the price is already good and we're leaving it where it's at". No counter,= no offer to negotiate, places like this are often content to let listings s= it for years. So unless I want to spend 2X what I probably should spend, to g= et my hands on 5 lower case letters in a blue font, I'm stuck. :)<= /u>

This SBX-251 looked to have dual-footprints. There was a se= t of pads that look like they would have accommodated the socket. If I did w= in the lottery and decided I had $200 I was willing to burn, I'd d= efinitely reverse engineer the netlist and send the schematic your way. :)
=
Scott

On Sun, May 21, 2023 at 5:36=E2=80=AFPM <craig@sbc-85.com> wrote:
Hi Scott,

pretty much a= ll the bubbles I have purchased loose have been dead, so I generally advise a= gainst buying bubbles that are not mounted in a board. Bubbles that ar= e mounted in a board seem to fair much better ( as long as they were working= when taken out of service of course). the board helps protect them fr= om static and other abuse. That said, I am very cheap and I usually on= ly buy boards /bubbles when the price is low enough that I am OK with it bei= ng DOA.

Interesting that the SBX-251 is the 7110AZ version. = I would need to check again, but I do not think I have any 251 that are the= Z version of the bubble. I am sure that I don=E2=80=99t have schemati= cs for the SBX-251 with Z bubble.
&n= bsp;
as for pricing, I did a quick s= earch of my emails to /from ebay sellers --- I see where I declined an= offer to buy a SBX-251 board for $88, so when I was in the market for them I= thought that was too much. I also see that there was one =E2=80=98buy= now=E2=80=99 priced at $45 plus shipping but I do not know if I bought that= one or not. if I didn=E2=80=99t but it, I probably should have b= ecause I think that is a good price even considering it was a =E2=80=9Cno-re= turn=E2=80=9D offer.

So your $200 fellow is a bit too proud of hi= s board for my budget, but if it came with a user=E2=80=99s manual or schema= tics it would pique my interest much more=E2=80=A6 not to the tune of $200 b= ut certainly $100 if it had documentation.. and that is only because I do no= t have any documentation as recent as the Z version.

If you are a= ble to get it for a reasonable price, if you are only interested in the bubb= le, I would be interested in getting the board off you.

hope that w= as helpful

<= p class=3D"MsoNormal">regards
craig<= u>

From: Sco= tt Baker <smbaker@= gmail.com>
Sent: Sunday, May 21, 2023 4:38 PM
To: SBC-85 <craig@sbc= -85.com>
Subject: Re: [Tindie Community] [PM] Order status<= u>

<= p class=3D"MsoNormal">Thanks Craig,

BTW, I did ma= nage to find an intel-branded 7110AZ on a SBX-251, but seller wants ~ $200 o= n it and isn't interested in offers. I assume that 1) odds of the memory its= elf being viable based on your experience are poor, and 2) the price is too h= igh? What have you paid for such things in the past?
=

Thanks,
Scott

<= div>
On Sat, May 20, 2023 at 3:40=E2=80=AFPM SBC-85 <craig@sbc-85.com> wrote:<= u>
Scott, you can m= odify and redistribute my code to your hearts delight. Please just reference= the source in the header.

Lately Digi-Key h= as been (evidently using calculated weight/size) printing a label and giving= a tracking number up to three days before the order is actually fulfilled a= nd ships.
Regards<= u>
Craig=
=
On May 20, 2023, at 2:52 PM, S= cott Baker <smbake= r@gmail.com> wrote:
=EF=BB=BF
Thanks for looking, Craig. I'll have to keep my eye= s out for an Intel-branded one. If you do ever turn one up, please let me kn= ow. :)

=
I'll make sure to send you a pointer to th= e video once it's out. I'm a little bit delayed this weekend as one of my di= gikey packages is taking the scenic route getting here. Maybe next weekend.<= u>

<= /div>
What are the license restrictions for using= /modifying/redistributing your code (on a non-commercial / hobbyist project)= . I see copyright headers, but no license restrictions. Ideally I'd make my m= odifications and push to to my github, but don't want to run afoul of licens= e if you don't permit redistribution.

I may b= e back for another bubble kit or two assuming these ones work out well for m= e -- I have a few projects in the back of my mind.

Scott
<= /u>
On Fri, May 19, 2023 at 4:21<= span style=3D"font-family:Arial,sans-serif">=E2=80=AFPM <craig@sbc-85.com> wrote:<= u>
Hi Sc= ott

I have about another 10 of the memtech labeled kits. lo= oking through the plastic at the date code on the bubble, about half of thos= e with date codes of 86 and the rest date code of 87. I do not know wh= en the brand marking transfer occurred, I believe it was sometime in 86 for t= he 1Mbit and maybe a little later for the 4Mbit. Just like the o= nes I sent you, the =E2=80=9Cstatic sensitive=E2=80=9D label is placed right= over the top of the bubble so I can not see the branding of the chip itself= . if I were a betting man, I would say they are all memtech.=

look at the back of the ones you have=E2=80=A6. where it says Philippines=E2= =80=A6. on some of the ones I have there is a lower case intel =E2=80=9Ci=E2= =80=9D just to the left & superscript to the =E2=80=9CP=E2=80=9D, maybe e= ven merged with the P actually. The date code and this iPhillipi= nes is visible through the plastic on the back if that turns out to be a hin= t.

Of course any 1Mbit in the 7110 leadless will be intel brande= d, they had switched to the 7110A pin version before going over to memtech.&= nbsp; I do not have the any of the BPK70 (leadless) kits, only the BPK70A (p= inned version) kits. I am not sure there was a leadless BPK70 kit.&nbs= p;

I do have a couple of BPK-72 which was the bubble proto= type kits, I think one or both of those are leadless carrier version. T= hey will be part of my estate if you can wait that long.

There wa= s a BPK-72 kit in Canada on ebay the other day. it went for $445, but n= ot to me. I would really like to know who bought it because I would li= ke a bit of information from them. That one had an intel branded 7110A= bubble. eBay item number:125767052713 sold a few months ago.

I have a number of 4Mbit bubbles in some intel bubble PC boards.&n= bsp; I doubt that I will ever make a 4Mbit version of the SBC-85 bubble boar= d so someday I will part ways with most of those.

I am not the most= organized person so it is possible that I have some in a box or drawer that= I have forgotten about. I also have one or two intel iSBX boards and i= magine those may be intel branded bubbles. I do not recall if they are= 7110 or 7110A bubbles.

Sorry I can=E2=80=99t be more help. = let me know where to watch your video blog, I am always interested in heari= ng about bubble projects.
<= /u>
regards

craig<= /p>

&nb= sp;

From:= scott baker <= smbaker@gmail.com>
Sent: Friday, May 19, 2023 1:33 PM
<= b>To: SBC-85 <c= raig@sbc-85.com>
Subject: Re: [Tindie Community] [PM] Order= status
=
If we can find a live one, I=E2=80=99d prefer= that to a dead one, but I can still find some use for a dead one =E2=80=94 I= =E2=80=99ll be making a video blog post on this at some point, and the intel= ones do look nice and I can tell a little bit of a story.
=

The three memtech kits you have left on tindie, are they the remai= nder of your inventory?
&= nbsp;
Scott
Sent from my iP= ad

On May 19, 202= 3, at 12:32 AM, SBC-85 <craig@sbc-85.com> wrote:
=EF=BB=BF=
Hi Scott,

I will look through them to see what I have (unless the sticker makes it i= mpossible to see the bubble chip itself without opening the package).=

<= div>
Are you looking for dead or alive? I freque= ntly see loose chips on eBay, but most or all the loose ones I have purchase= d have been dead.
<= u>
Regards
=
Craig

On May 18, 2023, at 11:15 PM, Scott Baker <smbaker@gmail.com> wrote= :
=EF=BB=BF
Hey Craig,

I was wondering if any of the kits yo= u have remaining are known to have Intel-braded/labeled bubble memories in t= hem? Alternatively, if you had any loose modules with Intel branding on them= , I could be interested in picking one up.

= BTW, the package arrived last week, all looks great.
=

Scott

On Fri, May 5, 2023 at 10:4= 1=E2=80=AFPM Scott Baker= <smbaker@gmail.co= m> wrote:
Thanks a lot, and I'm looking forward to it!
<= p class=3D"MsoNormal">
Scott
<= u>
On Fri, May 5, 2023 at 9:14=E2=80=AFPM SBC-85 <craig@sbc-85.com> wrote:<= u>
Thanks for= the reminder. Shipped, and tracking number on tindie

On May 4, 2023, at 9:29 PM, SBC-85 &= lt;craig@sbc-85.com> wrote:
=EF=BB=BF
Hi Scott,
&nb= sp;
Yes, sorry, I forgot a= bout your order. I will send it out tomorrow and post the tracking number.

Regards

Craig

Begin forwarded message:
<= p class=3D"MsoNormal" style=3D"margin-bottom:12pt">From: scott baker v= ia Tindie Community <donotreply@tindie.com>
Date: May 4, 2023 at 8:25:27 P= M PDT
To: cr= aig@sbc-85.com
Subject: [Tindie Community] [PM] Order statu= s
Reply-To: scott baker via Tindie Community <discuss+7d42f15c87f25561f8c3ec448c69a4ad@tindie.com><= /p>
=EF= =BB=BF
<~WRD0000.jpg>
smbaker
May 5
Hey Crai= g, I noticed my order for some bubble memories and other goodies hasn=E2=80=99= t shipped yet. Just checking in for an ETA, and to make sure you got a notif= ication on the order from tindie. Thanks, Scott. [Sent from Store Page]

Visit Message o= r reply to this email to respond to smbaker, ccandrews.
To= unsubscribe from these emails, click here.<= /span>
&nb= sp; &n= bsp; &= nbsp;
<~WRD0000.jpg>
<= /div>
<= /div>
=