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My latest project is called SDD 99 and is both a multi-function expansion card and a PEB replacement. It's currently in the prototype stage and about 80% complete.

 

post-35214-0-51647200-1541964164.jpg

 

The SDD 99 features an SD-card based disk, 32 or 64 MB of SAMS-compatible RAM, Wifi and a remote file server, and various ports. This video shows how to use the SDD 99, but be warned, I suck at YouTube. :)

 

 

The SDD 99 uses an ARM Cortex M microcontroller and one SDR SDRAM IC. Programming the Cortex M has been both a breeze, and a nightmare. It's been super easy to create logic such as the cartridge emulation, but dealing with its peripherals such as SD, RAM, and Wifi has been major stumbling blocks that cost me months.

 

I started this project end of last year, mostly since I wanted to see what a Cortex can do. Of course I'm fully aware that TIPI has long since been released, but I never meant to compete with or best TIPI. In fact, I abstained from AA for the past view months, since I didn't want to learn too many facts about TIPI.

 

So, I'm aiming for completing this by next spring, but of course my original plan was to show the prototype in May. :)

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Amazing job, Ralph!

 

I am truly amazed at the amount of ingenuity with all these peripherals coming out. You have literally two chips doing everything on this board.

 

It's a great time to be in retro TI computing. And you're right... each peripheral has a different audience. And, then you have geeks like me that change things around all the time for different scenarios, so keep just about everything laying around in case I need it. :-)

 

 

 

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Hi Ralph!

Congrats on the announcement here!

Is it okay to publish the video recording from your presentation at the TI-Treff 2018?
I would have it prepared on youtube.com.

BR Klaus

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Is it okay to publish the video recording from your presentation at the TI-Treff 2018?

I would have it prepared on youtube.com.

 

Sure, go ahead. You can see then how much difference a month makes. :)

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Unreal..... this is the bees knees, as we say.

 

You have once again blown me away. :)

 

I would mostly be interested in this as an expansion card, and using it mostly as a Hard Drive. :)

 

I can't wait to see more information on this thing as it comes out. Thanks again, sir!

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Ralph, you basically created a true DOS for the TI with a hard disk implementation. Absolutely awesome!

Now you mentioned something about ports but don't give much detail. What kind of ports will this device have and will they be compati le with existing ones like RS232 and PIO?

Also will there be capability to run Basic and XB programs with the XLOAD command?

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Amazing job, Ralph!

 

I am truly amazed at the amount of ingenuity with all these peripherals coming out. You have literally two chips doing everything on this board.

 

It's a great time to be in retro TI computing. And you're right... each peripheral has a different audience. And, then you have geeks like me that change things around all the time for different scenarios, so keep just about everything laying around in case I need it. :-)

 

Thanks, but to be fair, there's an extra chip for the Wifi connection (not shown). It's a widely used ESP8266, and I absolutely hate it. :) There are other options, though. In fact, there's the W600, which is basically a Cortex M3 with Wifi. Unfortunately, I need at least M4, otherwise I'd really need only two ICs. ;)

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Ralph, you basically created a true DOS for the TI with a hard disk implementation. Absolutely awesome!

Now you mentioned something about ports but don't give much detail. What kind of ports will this device have and will they be compati le with existing ones like RS232 and PIO?

Also will there be capability to run Basic and XB programs with the XLOAD command?

 

Thanks! There's already a serial port, but right now I'm using it to log status and error messages. This thing will be TI-compatible, unless there is a reason not to be. :)

 

Then, I thought of PIO, if I can spare a few pins, and the rest would be general I/O pins, readable by CRU and one or two CALLs.

 

USB would be possible, but I don't know what to use it for. No, you cannot just plug in your Logitech mouse or MP3 player. :)

 

About BASIC programs ... Probably. The BASIC files are more or less a memory dumps, so they should be easy to transfer back. For XB, though, you could just use RUN, although I guess the filename would have to be static.

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I forgot to post a picture of the working SDD 99 connected to the side port.

 

post-35214-0-66575500-1542051035.jpg

 

The appendages are, from left to right, battery, serial connection, and Wifi chip (off the photo). Thanks to clever pin assignments, the LED is dead. :ponder:

 

Also, I put the side connector upside-down on the PCB. That's why the PCB is facing downwards.

 

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Cool but does it support anything in XB or is this 100% just TI Basic?

 

If that is the case it would exclude a insane number of programs and applications in XB?

Edited by RXB
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Cool but does it support anything in XB or is this 100% just TI Basic?

 

If that is the case it would exclude a insane number of programs and applications in XB?

 

 

I'm just guessing here, but with the insane size of the memory, the ability to load CARTRIDGES and his previous work on the FinalGROM, I'm thinking any BASIC in cartridge form should be loadable executable.

 

The ideas and possibilities are flooding into my head right now....

post-35324-0-19211000-1542072488.jpg

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Cool but does it support anything in XB or is this 100% just TI Basic?

 

If that is the case it would exclude a insane number of programs and applications in XB?

 

No, that's not my plan. But subprogram parameter parsing in XB is somewhat different than in BASIC, and I haven't implemented those changes yet.

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As mentioned above, would love this as a PEB card.

 

For a PEB card, you would set the CRU to >1000 (before the TI controller), and then configure which DSK devices you would want to use. The other drives would then be passed to the real floppy controller.

 

If you don't want to use the DSK devices of SDD 99, you can choose any CRU you want.

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The ability to load cartridge images from files is really cool, I assume it works for ROM carts only? What if you have a GROM only cart in the physical slot, could you still load a ROM cart from the SDD99? Do you also allow RAM mapping into the >6000 region using the SAMS mapping registers?

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Sure, go ahead. You can see then how much difference a month makes. :)

 

Part 1:

Part 2:

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I am impressed by what looks like near-instantaneous file loading / IO speeds. Very nice.

 

That's because the data read from the uSD card and written into the RAM stays on the SDD and does not involve the TI 99 at all. OLDs, on the other hand, are just as slow as you know them, because the data has to be funneled into the VDP RAM by the TI 99.

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