Reverse engineer the SYEMB06?

HopefulDave · Unread post by **HopefulDave** » Fri Feb 03, 2006 12:16 am

Hi folks, does anyone have a SYEMB06 NVRAM/Flash card fitted to their
SY85? I can't find them anywhere, so I'm interested in possibly reverse-engineering it, and wonder if anyone could get me a decent jpg/bmp of the board from both sides, and a list of part numbers? I've got the kit to make double-sided PCB's, and *might* be able to produce a batch of 'em with NVRAM chips etc. as kits (or just bare boards and a parts list) if there was any interest, and if I can get enough info on 'em... I saw a mention in an old posting of some other folk looking into a non-volatile board for the '85, but it seems to have sunk without trace

It might even be possible to increase the non-volatile memory size, depends how Yamaha have presented the internal buses on the card connector, I guess?

Thanks,
Dave H.
(The engineer formerly known as Homeless)

Unread post by **Saul** » Fri Feb 03, 2006 1:47 am

Hi Dave. Welcome to the site.

Certainly sounds like a good idea. Plenty of people would be interested in non volatile memory for the 85. But...seeing as how they are rarer than hens teeth I'm not sure we have anyone on the forum who has one fitted. However I'll make this post a sticky so at least it won't dissapear into the ether. You never know, someone may pass by who has one

HopefulDave · Unread post by **HopefulDave** » Fri Feb 03, 2006 3:17 pm

Thanks, It seems to me that it can't be too much of a technical challenge (I've done similar with a coupel of obsolete parts in the past, and as to credentials, I used to be senior engineer with one of the smaller Austrian studio gear companies in their UK arm, working on digital delays and effects etc., built specialist hardware for the special effects industry) - if I can't cheat by making a copy/update of the real thing I could probably work from a combination of service manuals / schematics (if I can get hold of 'em) and parking a logic analyser on the card slot of my '85 - it'd be interesting / useful to hear from the guys who earlier made an attempt to clone the boards, if they're still around?

Dave H.
(The engineer formerly known as Homeless)

Clyde · Unread post by **Clyde** » Fri Feb 03, 2006 3:26 pm

Hi Dave,
Welcome to the Forums! Can't help you too much as I don't have an SY85, but I do have SYEMB05 boards in my SY99, I know that they are different from the SYEMB06 boards for the SY85 and will not work in the SY85. There is rarely an SYEMB06 board on eBay, there are some possibilities for schematics at some sites on the net, I don't have any links handy but will look for them later. I think demand was low for the SYEMB06 boards because most people opted for the cheaper computer ram and Yamaha consequently did not produce many of these boards.
Clyde

Clyde · Unread post by **Clyde** » Fri Feb 10, 2006 12:41 am

Hi Dave,
Yesterday I emailed the folks at Musitronics to see if they might be able to direct us to some info/schematics or if they knew of any sources other than eBay. Hope to hear from them soon. They do make a RAM expansion for the SY99 that works with the SYEMB05 boards. I'll post any info as soon as I hear back from them.
Clyde

shadowmask · Unread post by **shadowmask** » Sat Mar 25, 2006 6:35 pm

Hi Clyde,

Did you ever get any info from the guys at Musitronics?

Clyde · Unread post by **Clyde** » Sat Mar 25, 2006 6:57 pm

Not a peep out of them. I've been able to find schematics for lots of things, but nothing for the SYEMB06 memory boards.
Clyde

shadowmask · Unread post by **shadowmask** » Sat Mar 25, 2006 9:41 pm

I've been toying with the idea of making one of the SYSEMB06 boards as discussed earlier in this thread, but without the connector pinouts I'm kinda in the dark like everyone else.

It MAY BE possible to mod the SY85's internal 512KB to become non-volatile provided the SY doesn't clear it all by default on power-on.

EDIT:

Forget that idea - due to the type of internal RAM (PSRAM) this would be too much hassle to implement

Clyde · Unread post by **Clyde** » Sun Mar 26, 2006 12:52 am

I've got some posts out in other places looking for a schematic, we'll see what turns up.
Clyde

nmorvay · Unread post by **nmorvay** » Fri Mar 31, 2006 5:28 am

Hi HopefulDave,

I hope you haven't given up on your little project. I could always use more non-volatilve ram. What is it exactly you need? I do have one SYEMB06 chip installed, though I could never find a second. If I can help in anyway, let me know.

Nick

shadowmask · Unread post by **shadowmask** » Wed Apr 12, 2006 11:28 am

Guys,

I've been working at this for a few weeks and have got to the stage of building a prototype but have come to one major hurdle - trying to source connectors that will plug into the SYEMB06 D-type plugs on the SY's main board. I guess Yamaha had custom connectors made for the SYEMB06 module. These 52-pin things are obscure!

Time for possible Plan B option..

Plan B is to remove the onboard PSRAM chips and replace these with proper SRAM chips and tie them into the SY's internal battery giving 512KB of non-volatile ram. Luckily I have SMD reworking tools at my disposal so this is a relatively easy operation. The SRAM chips are sitting here in front of me so over the next few weeks I will try this out on my SY.

Optional Plan B+ is to make a 1MB board that will connect to the underside of the SY's SYEMB06 socket pins with wires to take the total non-volatile memory up to 1.5MB. Possible but time consuming!

Now the big question for SY85 owners is... if these obscure connectors cannot be found would you be prepared to send the CPU board of your 85 away to have Plan B and optionally Plan B+ applied to it?

Baz

shadowmask · Unread post by **shadowmask** » Sat Apr 15, 2006 12:41 pm

UPDATE..

The 'Plan-B' mentioned in my previous post has been tried and didn't work

Although the new SRAM ICs work 100% with the SY I guess the firmware doesn't check the integrety of the onboard memory on power-up. I had hoped that there was some sort of sample allocation table stored in the onboard memory that the SY would find again on power-up. I knew it was going to be 50/50 so no real disappointment.

Good news - the connectors have been found on a few UK websites and several emails have been sent. Hopefully good results will come from there

Baz

Unread post by **Saul** » Sat Apr 15, 2006 12:55 pm

Just wanted to say well done baz! Nice to see someone so dedicated to upgrading the SY. There are so many people out there who love the SY85 and would happily pay for a non volatile memory upgrade....especially if it were cheaper than Yamaha's now, very rare option

shadowmask · Unread post by **shadowmask** » Mon Apr 17, 2006 2:07 pm

UPDATE..

I've been busy over the weekend trying to get this prototype thing up and running. As you can see from the 2 photos in the link below it isn't the prettiest thing you've ever seen. I suspect the Yamaha version is a little tidier!

http://smg.photobucket.com/albums/v213/ ... 1/SYEMB06/

I loaded in a sample from floppy into non-voliatile memory and after 10 mins of power-off the sample was still there. Removing one of the SRAM 'chip select' leads off the prototype caused corruption on sample playback so the sample is definitely in that lump of glue somewhere!

Baz

Clyde · Unread post by **Clyde** » Mon Apr 17, 2006 2:50 pm

Baz,
I'm sure many other prototypes have looked equally bad, after all it is a work in progress. Sounds like you are getting closer, it will come together at some point. Keep up the good work!
Clyde

Reverse engineer the SYEMB06?

Reverse engineer the SYEMB06?

Thanks, Saul