Mega-Cart

nbla000 · Post by **nbla000** » Tue Sep 09, 2008 2:19 am

Hey Anders be careful

Please consider that it is the very first prototype with a lot of wires insted of tracks, the MegaCart #2 use wires too but is much more robust, actually on MegaCart #3 and #4 prototypes there are just few wires for PCB fixes purpose.

orion70 · Post by **orion70** » Tue Sep 09, 2008 2:38 am

Anders' inattention has made you anxious?

Mike · Post by **Mike** » Tue Sep 09, 2008 2:38 am

I deleted roughly 8 copies of nbla000's posting above. Maybe you should check your browser settings.

Greetings,

Michael

carlsson · Post by **carlsson** » Tue Sep 09, 2008 3:27 am

It can happen if the server is slow and you hit reload just in case the message otherwise would be lost.

After reseating the SRAM, I got a funny set of favorites but I suppose it was due to random.

nbla000 · Post by **nbla000** » Tue Sep 09, 2008 4:16 am

carlsson wrote:After reseating the SRAM, I got a funny set of favorites but I suppose it was due to random.

If you mean reset the preference (so NVRAM) using the service menu by holding CTRL key on boot, you must get no favorites and just 2 early menu items, Disk Utility $A000 and EasyLoad+.

PS: Sorry for last multiple replies, i got a lot of PHP error when submited replies.

carlsson · Post by **carlsson** » Tue Sep 09, 2008 5:03 am

Well I got Dancing Bear (!) and Frogger '07 on the Early Menu, plus Avenger as my only favorite. It probably was true random.

6502dude · Post by **6502dude** » Tue Sep 09, 2008 6:49 am

I suspect that when NVRAM was loose that random data got written as favourities.

As NBLA000 noted, this can be cleared via maintenance menu.

You can also backup your favourities to disk and restore them via this menu.

6502dude · Post by **6502dude** » Wed Sep 17, 2008 7:11 pm

I had a lot of issues come up in August which diverted my attention away from MegaCart.

However, I have made some progress lately to get this project into production.

MegaCart prototype (fabricated PCB) is currently being extensively tested in "PAL" land. I am still doing tests with MegaCart #4 in "NTSC" land.

I have reconfigured my home made eprom burner to burn OTP eproms in PLCC form factor. This will allow PCB size reduction.
I ordered some of the OTP chips yesterday from Texas, they arrived today, and I burned them tonight succesfully.

This is image for comparison of chip sizes, with existing eproms on left and PLCC OTP chips on right.

I have also sourced supply of all parts needed for production with objective of making final layout entirely with SMT components.

Next step for me is final revision of schematic and PCB layout size reduction.

ral-clan · Post by **ral-clan** » Wed Sep 17, 2008 9:18 pm

Just a small note on my part: I sent the graphics for the label and box to VicUser to do some test prints for me. He has access to industrial type high-grade printers. This will help determine how close the actual colours are (vs. on-screen colours in my DTP application).

Still to be determined are the cost of printing labels and boxes or just offering a pdf for everyone to print his or her own.

eslapion · Post by **eslapion** » Wed Sep 17, 2008 10:14 pm

6502dude wrote:I have reconfigured my home made eprom burner to burn OTP eproms in PLCC form factor. This will allow PCB size reduction.
I ordered some of the OTP chips yesterday from Texas, they arrived today, and I burned them tonight succesfully.

Please don't take this as an insult or attack.

About a year ago I suggested that you should use OTPs to reduce the cost of production. Maybe I misunderstood you but you seemed to say that was not a good idea.

Now you go along with it which I think is a good idea.

Using the PLCC form will also reduce footprint which reduces the cost of production of PCB.

I also believe it should be possible to use a single 16Mbit ROM or EPROM. Then again, considering the design, it might prove quite difficult to achieve and involve adding too much logic chips.

I think it should be possible to have the ROMs replaced with chips which are programmable or modifiable. Maybe using NVRAM would be risky. Perhaps flash memory chips which happens to be really cheap could be used instead of ROMs or PROMs.

Also, the possibility still exists to convert your design, while maintaining exactly the same schematics, to be made into a full surface mount design. I guess this would make it small enough to fit in a standard VIC cart case as it would have just about the same size as a VIC-1110/VIC-1111 RAM expansion.

I believe this last suggestion would make a lot of people very happy.

That's what I did on the Flashcart and I also placed parts on both sides of the board to minimize footprint. The final board was slightly smaller than an original 3K RAM expansion board.

nbla000 · Post by **nbla000** » Thu Sep 18, 2008 6:12 am

ral-clan wrote:Still to be determined are the cost of printing labels and boxes or just offering a pdf for everyone to print his or her own.

I wish to sell the MegaCart with labels and boxes, 6502dude has a preorder list so we may estimate costs, our shot at the moment is to reduce the PCB to fit it in a standard vic cart case with just an hole for the reset button.

Custom cart case are antiaesthetic if use generic solutions or very expensive if you order a specific case from a firm, Vic cart cases are commons and user like this solution so our intent is to absolutelly reduce PCB to fit it inside a Vic cart cases just like 8/16k cart expansions.

6502dude · Post by **6502dude** » Thu Sep 18, 2008 6:54 am

eslapion wrote:About a year ago I suggested that you should use OTPs to reduce the cost of production. Maybe I misunderstood you but you seemed to say that was not a good idea.

I found a source for eproms that was cheaper than OTP.
Switching to PLCC OTP actually raises production cost, but it is a compromise to save PCB space.

I also believe it should be possible to use a single 16Mbit ROM or EPROM.

See - http://sleepingelephant.com/ipw-web/bul ... c&start=60

I think I could find another 3 or 4 times this same question has been raised and answered.

I think it should be possible to have the ROMs replaced with chips which are programmable or modifiable. Maybe using NVRAM would be risky. Perhaps flash memory chips which happens to be really cheap could be used instead of ROMs or PROMs.

Sorry, after 1.5 years into this project, plus many hours spent doing testing and software development, there will be no more changes to hardware design.

ral-clan · Post by **ral-clan** » Thu Sep 18, 2008 6:33 pm

nbla000 wrote:
ral-clan wrote:Still to be determined are the cost of printing labels and boxes or just offering a pdf for everyone to print his or her own.
I wish to sell the MegaCart with labels and boxes, 6502dude has a preorder list so we may estimate costs, our shot at the moment is to reduce the PCB to fit it in a standard vic cart case with just an hole for the reset button.

Custom cart case are antiaesthetic if use generic solutions or very expensive if you order a specific case from a firm, Vic cart cases are commons and user like this solution so our intent is to absolutelly reduce PCB to fit it inside a Vic cart cases just like 8/16k cart expansions.

It would be cool if there was a site like lulu.com (prints small runs of self-published books, magazines, CDs etc) for labels and boxes (lulu.com doesn't do these). They do high quality work for pretty cheap and will do any number of prints.

I don't like the idea of sending printing work off to China to be done, but perhaps that's the only viable option for this kind of work if we want it to look "real" and be affordable for ca. 200 units. I don't even know of an on-line service that will do this, though.

Does anyone know the people from AtariAge.com? They seem to have found a solution for the packaging of their custom cartridge runs.

Wonder-Boy · Post by **Wonder-Boy** » Fri Sep 19, 2008 12:26 am

Kenz from Psytronik software has had similar things printed. Maybe he knows something about this. It's not labels but tape covers.

http://www.binaryzone.org/psytronik.php

eslapion · Post by **eslapion** » Fri Sep 19, 2008 3:00 am

6502dude wrote:I found a source for eproms that was cheaper than OTP.
Switching to PLCC OTP actually raises production cost, but it is a compromise to save PCB space.

This is the cheapest source I have found for new 8Mbit OTPs that are directly suitable to your hardware design:

http://www.mouser.com/Search/ProductDet ... EuBQ%3d%3d

They are less than 5$ each when purchased in batches of 100 or more.