Jump to content
ralphb

The FinalGROM 99

Recommended Posts

Excuse my ignorance on TI specs, I am new to this world of 99/4A and have just started playing around with my now working unit. As far as memory goes, even after I acquire the FinalGROM 99, will I still need to add a sideport 32K or something similar in order to run some of the roms?

 

 

 

 

Share this post


Link to post
Share on other sites

Excuse my ignorance on TI specs, I am new to this world of 99/4A and have just started playing around with my now working unit. As far as memory goes, even after I acquire the FinalGROM 99, will I still need to add a sideport 32K or something similar in order to run some of the roms?

 

 

 

 

Yep

 

Sent from my LG-H830 using Tapatalk

Share this post


Link to post
Share on other sites
Finally. This is it:


post-35214-0-64011500-1499611887.jpg


You may notice a few last-minute changes to the final prototype. The FinalGROM 99 now uses plain SD sockets, although you can still fit an Arduino shield if you want. Also, a second reset button resets the TI 99. This is useful for programs that don't react to FCTN-=. Finally, the 5V SRAM was replaced by its 3.3V couterpart, which is cheaper and easier to get.


As already mentioned, with only a few modifications, the FinalGROM 99 fits a standard cart shell.


post-35214-0-73345900-1499611901.jpg


You can also combine both reset buttons by getting a DPST switch for your case.


I updated the homepage to include the additional hardware features and some software changes I did (mostly, advanced modes, help viewer texts, and image dumping). The latter allows you to write the contents of the image in SRAM back to SD cart. This is useful for saving high scores, progress, or preferences.


You'll also find ordering information on the homepage. Please allow a few days for me to reply, especially in the beginning. While the boards are mostly complete, I need to add a few components, and, more significantly, program and test the final carts.


Thanks go to Jim (brain) for nudging me to use real SD sockets and introducing me to a cheap model, and to Eric (speccery) for analyzing an electrical program on the first prototype!





EDIT: added links

Edited by ralphb
  • Like 21

Share this post


Link to post
Share on other sites

 

The latter allows you to write the contents of the image in SRAM back to SD cart. This is useful for saving high scores, progress, or preferences.

That sounds super useful! Thanks for adding that.

Share this post


Link to post
Share on other sites

Me too! I've also got a new 99/4A that can't wait for this to be plugged into it. Combined with the nanoPEB, I'm *really* excited to get everything up and running.

Edited by Casey

Share this post


Link to post
Share on other sites

Why don't you get your SD card connectors from mouser or the sorts?

 

Look here:

 

http://www.mouser.com/Connectors/Memory-Connectors/Memory-Card-Connectors/_/N-axj8k?P=1yzxfx6&Ns=Pricing|0

The post's intention is admirable, but the cheapest Mouser option in the link is more expensive than the one he is currently using, so moving to a Mouser sourced unit would drive pricing up.

 

It sounds like there's a 100 order option on this device, so I recommend he have them professionally assembled. I'd hate to think he's planning to hand solder them :-/

 

jim

Edited by brain
  • Like 1

Share this post


Link to post
Share on other sites

The post's intention is admirable, but the cheapest Mouser option in the link is more expensive than the one he is currently using, so moving to a Mouser sourced unit would drive pricing up.

 

It sounds like there's a 100 order option on this device, so I recommend he have them professionally assembled. I'd hate to think he's planning to hand solder them :-/

 

jim

 

I just thought you could use that instead of ordering them off ebay. Not cheaper, rather if you went large scale you would definitely want to use this

 

Plus

  • It's a teensy bit more trustworthy than buying it off ebay
  • The parts can come in reels
  • And if they run out of stock you can ask the supplier for more or find a new supplier quite easily

Share this post


Link to post
Share on other sites

It sounds like there's a 100 order option on this device, so I recommend he have them professionally assembled. I'd hate to think he's planning to hand solder them :-/

 

Especially soldering SMDs. The only upside is you'd already be a professional by the end of the batch, ready to retire and everything

 

(it really wouldn't hurt to have some external assembler, or at the very least volunteer assemblers)

Edited by Gip-Gip

Share this post


Link to post
Share on other sites

 

 

I just thought you could use that instead of ordering them off ebay. Not cheaper, rather if you went large scale you would definitely want to use this

 

Plus

  • It's a teensy bit more trustworthy than buying it off ebay
  • The parts can come in reels
  • And if they run out of stock you can ask the supplier for more or find a new supplier quite easily

 

I believe he went with eBay because he could get a small quantity at a low cost, but he specified against a footprint I gave him, which can be purchased anywhere, and if he decides he needs high volume, I buy them direct from the manufacturer in 1000 unit batches. It's sad, but for the price Mouser is charging per unit, he can buy 1000 (with shipping) from the manufacturer and pay not much more than buying 100 from Mouser.

 

Now, your point holds more weight when it comes to the Xilinx and Atmel parts. It's not the cost in that case, or the supply, but the quality. As someone who had to replace 100 atmega1281 68 pin QFP packages on units because of counterfeit problems, (not my doing, the assembler tried a local source), it can get you.

 

I chose this footprint (and recommend it for anyone doing an SD design), because:

 

  • it's available on eBay, for small runs
  • it's manufactured by a bunch of vendors
  • I believe Digikey offers it (if you want the trusted vendor relationship)

 

#2 is important because I first did what you recommended, and used a 3M SD conn. Laid out the board, ran them, paid for the stencils, and then after a few runs, Digikey sends me a note that 3M discontinued that part. You never expect that to happen, and it was expensive. On a classic machine sales scales, even moreso. So, I decided to find a part made by a few vendors to hopefully alleviate the obsolete issue.

 

Jim

  • Like 1

Share this post


Link to post
Share on other sites

 

Especially soldering SMDs. The only upside is you'd already be a professional by the end of the batch, ready to retire and everything

 

(it really wouldn't hurt to have some external assembler, or at the very least volunteer assemblers)

I priced it out. If he can get 100 orders, the going rate is ~USD$0.016 per pad. At that rate, it is darn near impossible to do anything else. Or, to put it another way, Ralph's gift is in the design, not the assembly, so he would be ahead to contract out the assembly and spend the time working on firmware revisions and such.

 

I solder up prototypes, but nothing more. Once the design is proven, it's time to let the pros do it, with their pick and place machines, etc.

 

Jim

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...