Bocaram AT XMS/EMS memory card replica?

Discussion about old PC hardware.

Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-3-26 @ 18:41

I was thinking about what to do with my "halved" Bocaram AT card:
https://www.vogons.org/viewtopic.php?f=46&t=17341&start=27887

Fixing would be an option, but the result would not be of any collectors value and I am not going to use it as I already own enough other RAM-cards.

Therefore I would propose to desolder all components and use it as template to make a copy of the PCB? These cards are rather hard to get for a reasonable price. I know there is already a LoTech EMS-only card, but I think the BocaRAM has many advantages:

- Very nice looking full length card, much better retro look than the LoTech
- drivers and documentation available http://ps-2.kev009.com/bocaresearch/Drivers&Software/Archived/File_area_20/
- supports EMS and XMS
- up to 2.5 MB - should be enough for most applications
- 16 bit
- only using standard components, no special ICs. China BoM should be rather cheap
- no SMD soldering, very beginners-friendly
- optional daughter board for an even better look and up to 4 MB
- supports 4164 and 41256 DRAMs. Maybe the most difficult and expensive to get parts, but everybody using a 286/386 should have some available?
- Boca Research doesnt exist anymore, no trouble with copyright?

What do you think about the idea? Would anybody be interested in such card? Is it worth the effort or wasted time/impossible?

The bad part is: I am totally out of time and I would take months for desoldering work and I have no experience so far with PCB designing.

Therefore, anybody interested in doing this fun project to speed it up? I am willing to ship the card for free :-)

IMG_2683r.jpg

IMG_2684r.jpg

IMG_2685r.jpg
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-3-26 @ 18:42

IMG_2687r.jpg

IMG_2688r.jpg
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Anonymous Coward » 2019-3-27 @ 00:25

If you're going to replicate, you might as well skip the ICs and use SIMMs or something more practical.
BocaRAM AT Plus would be more ideal, but it uses a proprietary ASIC.
Will the highways on the internets become more few?
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium
User avatar
Anonymous Coward
l33t
 
Posts: 3300
Joined: 2008-3-20 @ 05:37
Location: Shandong, China

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-3-31 @ 10:04

Sorry I dont have the knowledge to do any modifications... :-)

Nobody else interested? :-( For me these cards are very useful and interesting.

I think I will desolder the difficult to get / fragile parts (e.g. the DIP block) carefully and for the remaining parts I will try a heatgun-desoldering to not spend to much time on it. If a IC gets damaged it doesnt matter. Can test them in the TL866 afterwards and a replacement is not hard to get...
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-3-31 @ 17:33

yeahh...heatgun massacre :-/

Courios how many ICs surived the procedure :-D At least the DIP-switches are OK.

The PCB should be in sufficient good condition to be used as template.

Anybody an idea how to continue the best way..? ;-) I have dowloaded the trial of "Sprint designer".

But I dont like do redraw the the whole ISA connector. Is there anywhere a template I can use?

DSC_8301-bocades.jpg

DSC_8302bocades2.jpg
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-4-06 @ 14:14

Bocaram-A.jpg

Bocaram-B.jpg

Bocaram-C.jpg

Bocaram-D.jpg
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-4-06 @ 15:50

Update on this most important topic with huge interest ;-)

Above 1200 dpi scans of the blank PCBs.

Below: BoM :-D

Think in theory all is in place now to reconstruct this card..?

DSC_8348.JPG
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby FAMICOMASTER » 2019-10-05 @ 18:32

Don't mean to bump a dead thread, but I personally love my BocaRAM XT card, and my AST Advantage 128, and this is an excellent middleground. This could easily be a great project, and I'd love to see something like this come about.

I think coping the AT Plus might be overkill, because there's almost no chance that the ASIC is in production anymore. Something like this or the AST would be much easier, since they all use relatively standard logic chips that can still be purchased today. DIP would also be nice so us plebians with old soldering irons can still assemble them.

I would be willing to donate my BocaRAM XT to the research if need be. I also would not mind at all purchasing a board / components to build one or two on my own, I really would have liked to have the AT with the 2MB expansion!

Something else of note... If the card can be compacted at all during the design, a serial / parallel port would not be too difficult to build in, even just as a header along the top of the card. I think that would really add some value to someone looking to get into vintage machines, but maybe that's just me.

Good luck and keep us posted!
User avatar
FAMICOMASTER
Member
 
Posts: 221
Joined: 2014-8-09 @ 18:15
Location: United States of America

Re: Bocaram AT XMS/EMS memory card replica?

Postby Predator99 » 2019-10-06 @ 16:21

FAMICOMASTER wrote:Don't mean to bump a dead thread, but I personally love my BocaRAM XT card, and my AST Advantage 128, and this is an excellent middleground. This could easily be a great project, and I'd love to see something like this come about.

I think coping the AT Plus might be overkill, because there's almost no chance that the ASIC is in production anymore. Something like this or the AST would be much easier, since they all use relatively standard logic chips that can still be purchased today. DIP would also be nice so us plebians with old soldering irons can still assemble them.

I would be willing to donate my BocaRAM XT to the research if need be. I also would not mind at all purchasing a board / components to build one or two on my own, I really would have liked to have the AT with the 2MB expansion!

Something else of note... If the card can be compacted at all during the design, a serial / parallel port would not be too difficult to build in, even just as a header along the top of the card. I think that would really add some value to someone looking to get into vintage machines, but maybe that's just me.

Good luck and keep us posted!


Thanks for the encouragement! But I will not follow-up on this topic. There seems to be no interest and I own enough of these cards. Little disappointing, as such card is a must-have for a 286 owner. But main reason is that I dont know how to handle these PCB design programs, I didnt even find a template for 16-bit ISA connector.
So if anybody likes to do that - go on ;-)
Predator99
Oldbie
 
Posts: 1113
Joined: 2016-12-28 @ 19:09

Re: Bocaram AT XMS/EMS memory card replica?

Postby Anonymous Coward » 2019-10-07 @ 02:11

It seems not very difficult to find 2MB ISA memory cards for AT computers. You should build something more unique. For example, 8 to 16MB cards are pretty rare, and so are EMS 4.0 cards that can handle the full 32MB. Maybe a 48MB card should be ideal. 16 for the extended memory, and another 32 for the EMS.
Will the highways on the internets become more few?
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium
User avatar
Anonymous Coward
l33t
 
Posts: 3300
Joined: 2008-3-20 @ 05:37
Location: Shandong, China

Re: Bocaram AT XMS/EMS memory card replica?

Postby FAMICOMASTER » 2019-10-07 @ 02:39

I think something like the BocaRAM, which is all through-hole, would be best for assembly and hobbyist. Maybe an upgrade to support 1Mbit DRAMs or greater, as well as a daughterboard.
User avatar
FAMICOMASTER
Member
 
Posts: 221
Joined: 2014-8-09 @ 18:15
Location: United States of America

Re: Bocaram AT XMS/EMS memory card replica?

Postby cyclone3d » 2019-10-07 @ 03:22

Predator99 wrote:Thanks for the encouragement! But I will not follow-up on this topic. There seems to be no interest and I own enough of these cards. Little disappointing, as such card is a must-have for a 286 owner. But main reason is that I dont know how to handle these PCB design programs, I didnt even find a template for 16-bit ISA connector.
So if anybody likes to do that - go on ;-)


Here are some ISA card templates for anybody who is interested.
https://designcontent.live.altium.com/TemplateDesigns/ISA

Converting files to the PCB design software of your choice can be a pain.. but I have done it before. That's how we got the SIMMCON revival RAM upgrade for AWE64 going.
User avatar
cyclone3d
l33t
 
Posts: 3396
Joined: 2015-4-08 @ 06:06
Location: Huntsville, AL USA

Re: Bocaram AT XMS/EMS memory card replica?

Postby FAMICOMASTER » 2019-10-07 @ 03:56

You know what would be a great combination card?

EMS/XMS expansion with an AdLib clone built on. AdLibs and proper clones are hard to find, so are good E/XMS cards, why not make them 2 in one?
Would have been a killer card in the day, I'm sure.
User avatar
FAMICOMASTER
Member
 
Posts: 221
Joined: 2014-8-09 @ 18:15
Location: United States of America

Re: Bocaram AT XMS/EMS memory card replica?

Postby Grzyb » 2019-10-07 @ 04:20

Anonymous Coward wrote:It seems not very difficult to find 2MB ISA memory cards for AT computers. You should build something more unique. For example, 8 to 16MB cards are pretty rare, and so are EMS 4.0 cards that can handle the full 32MB. Maybe a 48MB card should be ideal. 16 for the extended memory, and another 32 for the EMS.

Indeed, I could use eg. a clone of Orchid Ramquest 8/16.
But finding that Xilinx chip may be impossible...
Attachments
orchidramquest816.jpg
Grzyb
Member
 
Posts: 271
Joined: 2019-5-08 @ 13:47
Location: Poland

Re: Bocaram AT XMS/EMS memory card replica?

Postby FAMICOMASTER » 2019-10-07 @ 04:34

And finding a donor card to reverse engineer and copy the ROM from.
User avatar
FAMICOMASTER
Member
 
Posts: 221
Joined: 2014-8-09 @ 18:15
Location: United States of America

Re: Bocaram AT XMS/EMS memory card replica?

Postby Grzyb » 2019-10-07 @ 05:35

So yes, the idea of a brand new 48 MB card seems more viable:
- support for both 8- and 16-bit bus
- various conventional memory options: 64K..640K for early 5150 boards, 256K..640K for late 5150 and early 5160, 512K..640K for AT, possibly some others
- various upper memory options, maybe even 640K..704K or 640K..736K for those with mono or CGA adapters
- up to 15 MB of extended for AT machines
- up to 32 MB of expanded, with EMS 4.0 driver
- no need for SIMMs, all that 48 MB of DRAM soldered on

One card to satisfy all 8088 and 286 users, so there might be some demand...
Grzyb
Member
 
Posts: 271
Joined: 2019-5-08 @ 13:47
Location: Poland

Re: Bocaram AT XMS/EMS memory card replica?

Postby FAMICOMASTER » 2019-10-07 @ 05:46

Yep, and like I said, it might be a good idea to build a serial / parallel port or an AdLib clone or something in just so it will be multifunctional.

The only problem with LIM EMS 4.0 is that we would need to write a driver for it. A generic driver *probably* would not work without modification to it or the board.

I think if you weren't to include other functions, it might be nice to at least have headers for ports or a socket for the UART / OPL2 / whatever built in just to give you the option in the future.
User avatar
FAMICOMASTER
Member
 
Posts: 221
Joined: 2014-8-09 @ 18:15
Location: United States of America

Re: Bocaram AT XMS/EMS memory card replica?

Postby HanJammer » 2019-10-07 @ 06:28

Grzyb wrote:
Anonymous Coward wrote:It seems not very difficult to find 2MB ISA memory cards for AT computers. You should build something more unique. For example, 8 to 16MB cards are pretty rare, and so are EMS 4.0 cards that can handle the full 32MB. Maybe a 48MB card should be ideal. 16 for the extended memory, and another 32 for the EMS.

Indeed, I could use eg. a clone of Orchid Ramquest 8/16.
But finding that Xilinx chip may be impossible...


Xilinx XC3330 is standard off-the-shelf FPGA component, it shouldn't be much of a problem, but programming it - whole different story.

Grzyb wrote:So yes, the idea of a brand new 48 MB card seems more viable:
- support for both 8- and 16-bit bus
- various conventional memory options: 64K..640K for early 5150 boards, 256K..640K for late 5150 and early 5160, 512K..640K for AT, possibly some others
- various upper memory options, maybe even 640K..704K or 640K..736K for those with mono or CGA adapters
- up to 15 MB of extended for AT machines
- up to 32 MB of expanded, with EMS 4.0 driver
- no need for SIMMs, all that 48 MB of DRAM soldered on

One card to satisfy all 8088 and 286 users, so there might be some demand...


And reason behind 48MB of RAM in 286 would be...?
User avatar
HanJammer
Member
 
Posts: 480
Joined: 2018-8-21 @ 15:02
Location: Warsaw, Poland

Re: Bocaram AT XMS/EMS memory card replica?

Postby Grzyb » 2019-10-07 @ 06:39

FAMICOMASTER wrote:Yep, and like I said, it might be a good idea to build a serial / parallel port or an AdLib clone or something in just so it will be multifunctional.

But who needs such a multifunctional card?
I/O cards are plentiful, and so are AdLib-compatible sound cards.

Yes, there may be some PCs with few ISA slots, but those who keep such machines probably aren't very interested in expanding them.

Also, if one was to add sound to a memory card, there's this problem: some want AdLib, others want SB, or GUS, or PAS... impossible to satisfy them all.

Heh, there was UART option in some revision of XT-IDE - turned out to be a mistake, hardly anybody was interested...
Last edited by Grzyb on 2019-10-07 @ 07:09, edited 1 time in total.
Grzyb
Member
 
Posts: 271
Joined: 2019-5-08 @ 13:47
Location: Poland

Re: Bocaram AT XMS/EMS memory card replica?

Postby HanJammer » 2019-10-07 @ 06:48

Predator99 wrote:Therefore, anybody interested in doing this fun project to speed it up? I am willing to ship the card for free :-)


I would be interested in buying final product (PCB for installing my own ICs). In fact I was thinking about card like this recently (I have a lot of DIP memory chips I could use in card like this).

The fastest and least time-consumming way to make it would be sending it to China to have it reverse engineered - there are guys who specialize in this kind of things (even with way more complex multi-layer PCBs) - you send them the original PCB, they send you the files. On the other hand this being a very simple two layer board - it won't be a problem for somebody with a bit of experience and time to reverse engineer - now it's just a matter of removing the solder mask, scanning the bare PCB and then - recreating everything in KiCad or similar software.

This card would be excellent for the reasons you stated - it's period correct, ICs other than memory chips are just simple 74 logic...
Also the max memory size is perfect for this era PC.
Last edited by HanJammer on 2019-10-07 @ 06:58, edited 2 times in total.
User avatar
HanJammer
Member
 
Posts: 480
Joined: 2018-8-21 @ 15:02
Location: Warsaw, Poland

Next

Return to General Old Hardware

Who is online

Users browsing this forum: Google [Bot], knowledge [bot] and 14 guests