Flash ROM Cart

[Omega-TI]

These are my own labels for the FlashROM 99

if someone interested i can post there the images to print.

 

 

Well... like YEAH... post those PDF puppies!

[Omega-TI]

 

Damn.... anyone want to sell me a ROMOX case?

[ralphb]

Ksarul to the rescue!

 

As he pointed out, I goofed up when I copied the bank switch circuitry from the multi-cart in that I connected the capacitor to the wrong end of the resistor.

 

When I rewire the capacitor correctly, the disk test works just fine on my "bad" system, and response time seems improved overall.

 

And even better, it requires only a small modification to existing boards:

 

 

Just wanted to get this out. I'll add a more detailed description about the fix soon.

 

Thanks again, Ksarul, for saving my ass!

 

 

[+Schmitzi]

wow cool !! Is there anything for me that I can solder on my board now ?

 

 

 

[+jedimatt42]

I love it!

 

-M@

[+arcadeshopper]

Ksarul to the rescue!

 

As he pointed out, I goofed up when I copied the bank switch circuitry from the multi-cart in that I connected the capacitor to the wrong end of the resistor.

bankswitch.png

 

When I rewire the capacitor correctly, the disk test works just fine on my "bad" system, and response time seems improved overall.

 

And even better, it requires only a small modification to existing boards:

 

fix.jpg

 

Just wanted to get this out. I'll add a more detailed description about the fix soon.

 

Thanks again, Ksarul, for saving my ass!

 

 

 

Ksarul to the rescue!

[TheMole]

Ksarul to the rescue!

 

As he pointed out, I goofed up when I copied the bank switch circuitry from the multi-cart in that I connected the capacitor to the wrong end of the resistor.

bankswitch.png

 

When I rewire the capacitor correctly, the disk test works just fine on my "bad" system, and response time seems improved overall.

 

And even better, it requires only a small modification to existing boards:

 

fix.jpg

 

Just wanted to get this out. I'll add a more detailed description about the fix soon.

 

Thanks again, Ksarul, for saving my ass!

 

 

 

Excellent work, love the quick resolution on this. I haven't put mine together yet, you think that it'd be possible to do the fix without cutting the trace on an unassembled board?

[+Ksarul]

You could take the end of the capacitor that isn't connected to ground and solder it to the resistor lead that connects directly to the 377. It would work fine that way. . .so long as you don't connect the capacitor to the WE* signal on the bus side of the 68 Ohm resistor.

[Omega-TI]

I just want to clarify this before I do it. Are you saying all I need to do is take an X-ACTO knife to the trace highlighted and then just solder a piece of Kynar between those two points? If so, that IS an easy fix.

 

[00WReX]

I hope I have this correct.
From what Ksarul has mentioned, I have quickly put this together.
I hope this would be the modification without the need to cut a track.

Please correct me if I am wrong so that I can remove the diagram to avoid confusion.

 

Cheers,

Shane

 

EDIT: Added picture of the underside of the PCB for track reference.

Edited June 10, 2016 by 00WReX

[+Ksarul]

I took your drawing and added a little bit on the bottom--a green circle that identifies the two holes used to connect the capacitor to. You have it in the right position on the top, this just clarifies the bottom.

[+arcadeshopper]

easy mod to move the cap glad it was something simple!

 

Greg

[+jedimatt42]

I just want to clarify this before I do it. Are you saying all I need to do is take an X-ACTO knife to the trace highlighted and then just solder a piece of Kynar between those two points? If so, that IS an easy fix.

 

 

Since I have built myself 3 of these, I went ahead and tried this, per your drawing Omega, and it works for me.

 

-M@

[ralphb]

Are you saying all I need to do is take an X-ACTO knife to the trace highlighted and then just solder a piece of Kynar between those two points?

 

Yes, that's correct. You could also connect those two points, which is yet another variant.

 

 

For new boards the approach without cut will also work.

[Omega-TI]

 

Yes, that's correct. You could also connect those two points, which is yet another variant.

 

cut.jpg

 

For new boards the approach without cut will also work.

 

Thanks Ralf. Jim also confirmed in a PM. I'm up way past my bed time, I should have waited until tomorrow, but I just had to make the video....

 

https://www.youtube.com/watch?v=x_MUaKY_lF4&feature=youtu.be

[vectrexroli]

Thanks for the fix, it was quite easy to open my cartridge case and glue it back on using superglue again.

[+Schmitzi]

oh great, maybe I am ballsy enough (my latest learned english word )

and I to try to make that fix on my board later. But please, what is a KYNAR ?

 

And, did I have this error at all ? (pls see my pics from this FDC-Tests here in the thread)

But I assume this is a generally needed fix, of course.

 

thanks

xXx

[ralphb]

And, did I have this error at all ? (pls see my pics from this FDC-Tests here in the thread)

But I assume this is a generally needed fix, of course.

 

Well, no, you (and others) don't need the fix. Your system seemed to cope just fine, at least with your current configuration. Some controllers seem to be more tolerant than others.

 

On the other hand, you may consider this fix for your peace of mind. It may also speed up disk access, as I could imagine that some WE signals are missed and retried, but this is pure speculation on my part.

 

In your particular case I can do the fix for you when we do the DSDD disk thingy.

 

For others who absolutely have no one who can solder nearby I offer the following: If you got the cart from me, send me your cart at your cost and I'll fix it and send it back at my cost.

[+Schmitzi]

Great offer Ralph, thanks a lot

 

For me, as I have so many different systems and controllers, I just let it as is for the first time, to play around, and would ship it to you "this year"

(But I would be happy also to pay the ship back to me as you had enough efforts on all this great things so far,

or maybe we can "aggregate?" that with the next ship)

 

Now collecting BINs (and try to understand this Non-but-3-inverted-379 thing )

Is there any thread generally explaining how and why to convert files ? hint hint

 

xXx

[ralphb]

what is a KYNAR ?

 

From Wikipedia:

 

Polyvinylidene fluoride, or polyvinylidene difluoride (PVDF) is a highly non-reactive and pure thermoplastic fluoropolymer produced by the polymerization of vinylidene difluoride.

 

Alles klar?

[+Schmitzi]

Bahnhof

 

(railstation)

[ralphb]

There's a new, fixed Revision 2 of the PCB layout on GitHub now where the wiring has been swapped.

 

I also created a page that describes how existing Revision 1 boards can be fixed, i.e., converted to Revision 2 boards. Same as described here.

 

Finally, the homepage has been updated.

[+save2600]

First time ever hearing the word Kynar too... why not just call it a jumper lead or wire?

 

And just to clarify, this fix is only necessary for people using certain programs along with disk drives, correct?

[Omega-TI]

First time ever hearing the word Kynar too... why not just call it a jumper lead or wire?

 

And just to clarify, this fix is only necessary for people using certain programs along with disk drives, correct?

 

Sorry, Kynar is just another term for a type of wire, usually 30 AWG.

<< CLICK FOR EXAMPLE >>

 

Correct, the only people so far with an issue have been those with TI floppy controllers. If you can access your disk drive(s) with the FR99 in the TI, it would fall under the, "If it ain't broke, don't fit it" classification.

[+Lee Stewart]

... But please, what is a KYNAR ?

 

 

First time ever hearing the word Kynar too... why not just call it a jumper lead or wire?

 

Kynar is the very durable resin sheathing of wire-wrap wire. The name is a trademark that appears on the wire spool and has come to be used by some (many?) as the name for the wire itself.

 

...lee