Simple Electon MMC Interface

discuss both original and modern hardware for the bbc micro/electron
User avatar
flaxcottage
Posts: 4121
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Simple Electon MMC Interface

Post by flaxcottage » Mon Nov 12, 2018 8:20 pm

=D> =D> =D>
- John

Image

User avatar
davidb
Posts: 2820
Joined: Sun Nov 11, 2007 10:11 pm
Contact:

Re: Simple Electon MMC Interface

Post by davidb » Mon Nov 12, 2018 8:29 pm

That looks very useful. I'm sure there are a few people with Electrons but no Plus 1 expansions who would be interested in getting one of those. :)

With four spare I/O pins, surely you could connect directly to the SD card, or is level shifting needed?

Ramtop
Posts: 226
Joined: Tue Oct 23, 2018 1:40 pm
Contact:

Re: Simple Electon MMC Interface

Post by Ramtop » Mon Nov 12, 2018 10:43 pm

An improved and more polished design with a few added features I something I'd like to do, this one was really just designed as a way for me to learn about the Elk and it is pretty rough in all honesty. It has a couple of missing traces that I only noticed after the PCBs arrived :oops:

The SD card could be direct attached, the CPLD is an XC9536XL so the I/O is 3.3v. But this was really just a quick hack with the parts I had to hand, which happened to include a level-shifted MicroSD board.
Gary

User avatar
daveejhitchins
Posts: 5758
Joined: Wed Jun 13, 2012 6:23 pm
Location: Newton Aycliffe, County Durham
Contact:

Re: Simple Electon MMC Interface

Post by daveejhitchins » Tue Nov 13, 2018 8:15 am

Ramtop wrote:
Mon Nov 12, 2018 4:52 pm
Yes, indeedy, it does :D
=D> =D> =D> =D>

Dave H :D

User avatar
myelin
Posts: 932
Joined: Tue Apr 26, 2016 10:17 pm
Location: Mountain View, CA, USA
Contact:

Re: Simple Electon MMC Interface

Post by myelin » Tue Nov 13, 2018 6:39 pm

Ramtop wrote:
Mon Nov 12, 2018 4:52 pm
After acquiring my first Electron less than a month ago I set out to design a bit of hardware to bung in the back of it. Working on the old principle of walking before you run, I decided on a very simple one-socket sideways ROM card. At the weekend I got the board up and running and was pleased to be able to declare 'mission accomplished'!
Nice work! Great to see a new Electron CPLD project -- it's so rewarding to boot the machine and see everything come to life :)

Did you find a new source for the plug to connect your board to the Electron's expansion port? I bought a few old-stock ones from CJE/4D on eBay a couple of years back, but have never been able to find a modern model number for those.
Last edited by myelin on Tue Nov 13, 2018 6:40 pm, edited 1 time in total.
SW/EE from New Zealand, now in Mountain View, CA, making BBC/Electron hardware projects for fun.
Most interesting: Arcflash, FX2+PiTubeDirect Tube/Cartridge adapter, USB cart interface.

Ramtop
Posts: 226
Joined: Tue Oct 23, 2018 1:40 pm
Contact:

Re: Simple Electon MMC Interface

Post by Ramtop » Tue Nov 13, 2018 7:23 pm

I have to admit to doing a bit of a happy dance when the board fired up first time :)

Alas, no new source for connectors. I bought some cheap ones on Ebay that are intended for vertical through-hole mounting and just bent the pins inward and soldered the ends to the PCB pads. It looks ugly and probably won't stand up to more than a few tens of insertions, but for a test board it does ok. The sheer kludgery of it vaguely irritates me, though.

I've found a current 50-way socket with a right-angle through hole mounting that I'd like to use in future (CR22-50D-2.54DSA is the model) but it's out of stock everywhere and on a 16-week lead time. There's also the Sullins EBC25DREH which is sporadically available in small quantities from Digikey and may be usable as it has solder eyelets 1.57mm apart.
Gary

smokey
Posts: 19
Joined: Mon Mar 04, 2019 5:52 pm
Contact:

Re: Simple Electon MMC Interface

Post by smokey » Wed Mar 27, 2019 4:46 pm

Is anyone going to build these to sell as i am interested in one for my electron

James

User avatar
1024MAK
Posts: 10101
Joined: Mon Apr 18, 2011 5:46 pm
Location: Looking forward to summer in Somerset, UK...
Contact:

Re: Simple Electon MMC Interface

Post by 1024MAK » Wed Mar 27, 2019 5:59 pm

smokey wrote:
Wed Mar 27, 2019 4:46 pm
Is anyone going to build these to sell as i am interested in one for my electron

James
Do you mean the gadget from Ramtop?
His sales thread is here but currently he’s sold out. I don’t know if he plans to make any more.

Mark
Last edited by 1024MAK on Thu Mar 28, 2019 1:44 pm, edited 1 time in total.

Ramtop
Posts: 226
Joined: Tue Oct 23, 2018 1:40 pm
Contact:

Re: Simple Electon MMC Interface

Post by Ramtop » Wed Mar 27, 2019 7:00 pm

smokey wrote:
Wed Mar 27, 2019 4:46 pm
Is anyone going to build these to sell as i am interested in one for my electron
You've missed the boat for the moment; I've built loads of these cards, but just sold the last one yesterday.

More cards will be coming, but they'll be of an improved design that isn't quite ready yet.
Gary

User avatar
DaveLecky
Posts: 188
Joined: Mon Jul 08, 2019 7:52 am
Location: Airdrie, Scotland
Contact:

Re: Simple Electon MMC Interface

Post by DaveLecky » Sun Oct 27, 2019 8:06 pm

Hi Folks,

I’m trying to source a plug connection for the printer port of the Plus 1 for this project.

I’ve looked online and in the forum but can’t find anything.

My cables keep popping of at the worst times.

Can anyone help please.

Dave
Electron Plus 3 and plus 1, AP6 and Home made MMFS PP SD interface
Electron Plus 1 Pres AP3/4 with drive
Beeb issue 7 with IFEL 16 socket Rom/Ram board, IFEL SD card, Floppy interface
Master 128, BooBip multi OS,IFEL SD card
StrongA RPC, A3020

User avatar
daveejhitchins
Posts: 5758
Joined: Wed Jun 13, 2012 6:23 pm
Location: Newton Aycliffe, County Durham
Contact:

Re: Simple Electon MMC Interface

Post by daveejhitchins » Sun Oct 27, 2019 9:49 pm

DaveLecky wrote:
Sun Oct 27, 2019 8:06 pm
Hi Folks,

I’m trying to source a plug connection for the printer port of the Plus 1 for this project.

I’ve looked online and in the forum but can’t find anything.

My cables keep popping of at the worst times.

Can anyone help please.

Dave
Let me look, tomorrow, and I'll see what I have . . .

If you don't hear back from me please drop me a PM.

Dave H :D

User avatar
1024MAK
Posts: 10101
Joined: Mon Apr 18, 2011 5:46 pm
Location: Looking forward to summer in Somerset, UK...
Contact:

Re: Simple Electon MMC Interface

Post by 1024MAK » Mon Oct 28, 2019 8:41 am

DaveLecky wrote:
Sun Oct 27, 2019 8:06 pm
I’m trying to source a plug connection for the printer port of the Plus 1 for this project.

I’ve looked online and in the forum but can’t find anything.
Hi Dave

They are widely available, but the trick is knowing the correct search terms. Do you just want the connector, or do you want it already connected to a length of grey ribbon cable?
Try 26-way IDC like this on eBay

Mark

User avatar
DaveLecky
Posts: 188
Joined: Mon Jul 08, 2019 7:52 am
Location: Airdrie, Scotland
Contact:

Re: Simple Electon MMC Interface

Post by DaveLecky » Mon Oct 28, 2019 11:59 am

Hi Mark,

Found them thanks.

For some reason I presumed the printer port connector was a D-Type ...should have gone to Specsavers....

Thanks

Dave
Electron Plus 3 and plus 1, AP6 and Home made MMFS PP SD interface
Electron Plus 1 Pres AP3/4 with drive
Beeb issue 7 with IFEL 16 socket Rom/Ram board, IFEL SD card, Floppy interface
Master 128, BooBip multi OS,IFEL SD card
StrongA RPC, A3020

User avatar
daveejhitchins
Posts: 5758
Joined: Wed Jun 13, 2012 6:23 pm
Location: Newton Aycliffe, County Durham
Contact:

Re: Simple Electon MMC Interface

Post by daveejhitchins » Mon Oct 28, 2019 8:18 pm

DaveLecky wrote:
Sun Oct 27, 2019 8:06 pm
Hi Folks,

I’m trying to source a plug connection for the printer port of the Plus 1 for this project.

I’ve looked online and in the forum but can’t find anything.

My cables keep popping of at the worst times.

Can anyone help please.

Dave
Sorry . . . I don't seem to have an Electron Printer Port connector :shock: yet . . .

Dave H :D

User avatar
DaveLecky
Posts: 188
Joined: Mon Jul 08, 2019 7:52 am
Location: Airdrie, Scotland
Contact:

Re: Simple Electon MMC Interface

Post by DaveLecky » Mon Oct 28, 2019 9:05 pm

Hi Dave

Now I know what to order, I’ve got one coming from eBay......thanks for looking.

Dave
Electron Plus 3 and plus 1, AP6 and Home made MMFS PP SD interface
Electron Plus 1 Pres AP3/4 with drive
Beeb issue 7 with IFEL 16 socket Rom/Ram board, IFEL SD card, Floppy interface
Master 128, BooBip multi OS,IFEL SD card
StrongA RPC, A3020

User avatar
DaveLecky
Posts: 188
Joined: Mon Jul 08, 2019 7:52 am
Location: Airdrie, Scotland
Contact:

Re: Simple Electon MMC Interface

Post by DaveLecky » Sat Nov 30, 2019 8:17 am

Finally completed this project, I decided to go for an internal design.....

70C858EE-2F1F-42E0-9894-0D8DAD6806FE.jpeg

Dave
Electron Plus 3 and plus 1, AP6 and Home made MMFS PP SD interface
Electron Plus 1 Pres AP3/4 with drive
Beeb issue 7 with IFEL 16 socket Rom/Ram board, IFEL SD card, Floppy interface
Master 128, BooBip multi OS,IFEL SD card
StrongA RPC, A3020

User avatar
daveejhitchins
Posts: 5758
Joined: Wed Jun 13, 2012 6:23 pm
Location: Newton Aycliffe, County Durham
Contact:

Re: Simple Electon MMC Interface

Post by daveejhitchins » Sat Nov 30, 2019 8:52 am

=D>

Dave H :D

User avatar
roland
Posts: 3921
Joined: Thu Aug 29, 2013 9:29 pm
Location: Born (NL)
Contact:

Re: Simple Electon MMC Interface

Post by roland » Sat Nov 30, 2019 10:16 pm

Superb idea :idea:
FPGAtom: 512 KB RAM, Real Time Clock and 64 colours
MAN WOMAN :shock:

User avatar
0xC0DE
Posts: 633
Joined: Tue Mar 19, 2019 7:52 pm
Location: The Netherlands
Contact:

Re: Simple Electon MMC Interface

Post by 0xC0DE » Sun Dec 01, 2019 8:33 am

Very nice!
0xC0DE
"I program my home computer / Beam myself into the future"
:arrow: Follow me on Twitter
:arrow: Visit my YouTube channel featuring my demos for Acorn Electron and BBC Micro

mr-macrisc
Posts: 484
Joined: Wed Feb 07, 2018 3:35 pm
Contact:

Re: Simple Electon MMC Interface

Post by mr-macrisc » Sun Dec 08, 2019 1:17 pm

That’s very cool indeed :)

Post Reply

Return to “8-bit acorn hardware”