My hardware project :: GCart 2011

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TLovskog
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Post by TLovskog »

tokra:

As Mike pointed out, you would need to solder a few wires.

Basic usage
To only expand the memory internally (basically an internal 3k expansion) that all are usable by the VIC chip, you need to solder 3 wires and make one cut.

This will also give you RAM at $8000 where the original character ROM is. 4 banks + the original ROM switchable through software.

Extended Color
If you want the extended colormemory, you need to add another 6 wires, and make one cut.

Extra features
If you add another wire you will also have an autostarting firmware that will give you a menu for setting everything up, and possibly some extensions to the BASIC to make use of the hardware modification (if there are room, not really sure yet). No sys needed to enable it. It is all started automatically during reset.

With this you will also have the possibility to add another 4k of RAM usable by the CPU (and possibly BASIC, but I need to check if there are some hardcoded limitations) at $8000.
BR
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Post by Mike »

TLovskog wrote:With this you will also have the possibility to add another 4k of RAM usable by the CPU (and possibly BASIC, but I need to check if there are some hardcoded limitations) at $8000.
If that's supposed to map in the RAM during CPU access and the character ROM during VIC access, no problem. In a similar manner, you could also have BASIC programs running in BLK5.

If the screen memory then is moved down to $0400, this gives 35327 bytes free for BASIC. :shock:

Some programs might want to access the character ROM data though, so this should remain a switchable option.
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TLovskog
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Post by TLovskog »

f that's supposed to map in the RAM during CPU access and the character ROM during VIC access, no problem.
Yes. That was the idea. However, I was a bit uncertain if there was code in the BASIC somewhere that assumed that BASIC program and variables would be under $8000.
In a similar manner, you could also have BASIC programs running in BLK5.
Which of course answers the previous worries. Thanks!
Some programs might want to access the character ROM data though, so this should remain a switchable option.
It is. There are 4 registers at $9200-$9203 to control the expansion.
BR
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Post by Mike »

O.K., so I suppose the next two things on the agenda are then:

- a photo of the GCart 8K Internal mounted on the VIC-20 mainboard, with all connections, and

- a photo which shows the VFLI mode working, with one of the pictures on my example disks?

:)
Last edited by Mike on Sun Dec 02, 2012 5:57 pm, edited 1 time in total.
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Post by joshuadenmark »

Hi Thomas

Any news about this project?
Kind regards, Peter.
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TLovskog
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Post by TLovskog »

Hmm. Interresting timing. I have just started working on this again. It has been in the freezer for nearly half a year, because of time constraints.

As you might now Sony Ericsson (where I used to work) didn't do so good, so I took up an offer from another firm in Lund, Sweden. Just two months before a 70% (give or take) reduction in engineering at the Lund site. So now I work as system architect at Anoto. A small firm creating digital pens. However, although splendid work, it take alot of my time right now.

I am also quite involved in the local politics here in my municipal Kävlinge, and was recently elected as the chairman of the enviroment and building council. Another thing that takes alot of time. A bit more than anticipated actually.

Then of course ... my darn pool had to be finnished ...

Image

Well well ... excuses excuses ...

Another change is in the actual design, and this might sound strange and arrogant from a man who never seam to finnish ... it was to little of a challange. I said earlier that this had to be some sort of learning experience for it to be worth a couple of thousand EUR and many hours of work.

So I have redesigned it from nearly scratch.

Same functionallity, but I now use BGA and QFN packages for the main circuits, and 0402 for the RCL parts. I use a FPGA from Xilinx with softprocessors for the WiFi and memory management (mDDR2 and NAND flash) instead of PIC32. All this means I have been able to reduce the board to half size (and thus the cost of the PCB)

It also has the secondary effect that the memory size was increased nearly a thousand times to 64-512Mbyte (you can simply not buy smaller mDDR2 and at 1.78 USD I couldn't resist) ... which is extraordinary overkill. However, might be usefull for some serious acceleration of the BASIC when it comes to variables and arrays.

I also added an optional Commodore IEC serial port to be able to simulate the diskdrive the hard way.

The UI was moved to a smaller board and allows for 3 versions. 2 buttons plus LED, OLED 16x96 for icons or full graphic 96x64 OLED.

Image

The internal 8k board is also similairly reduced. It is now the size of the 24pin socket.

Image

Most of the design is far from finished, although most stuff is there. I am a bit worried about the power consumption, especially for the cartridge and internal expansion together.

A final change is that I will exchange Cadstar from Zuken and go all in on Altium Designer as my PCB design tool for my "hjemmefusk". That would create some rework, but will simplify things with the FPGA and softprocessor development. That will also complete my rebuild of "the lab".

Thanks for the continued interest.
Last edited by TLovskog on Thu Dec 19, 2013 4:13 pm, edited 1 time in total.
BR
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Post by joshuadenmark »

Hi Thomas

Thanks for this update, brand new design! I am impressed :D

Thank you for sharing this, can see you have lots of other real life stuff to keep you up in speed :lol:

Really like your new pool, mustncost at fortune to keep warm in cold sweden?
Kind regards, Peter.
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Post by TLovskog »

Hi,

Need some advice here.

To keep the cost down, of primarily the PCB, I have made it much smaller. Yet large enough to make use of all physical posibilities to fasten the board. I will use a ordinary commodore brown casing.

My problem now is the microSD card (big grey box below). The only place right now where it may be accessable is behind the 44 fingers. This means that ...
  1. The microSD card is only accessable when the cartridge is not inserted in the VIC 20.
  2. It is also a bit fiddly to remove / insert, since it has to be inserted deep enough to not collide with the 44 pin connector in the VIC 20, when the cart is inserted.
So I humbly ask the community what you would have done ...
  1. Yeah. This is ok. I would hardly change the card anyway.
  2. No way. And no freaking microSD card either, give me the larger SD card version easily accessable from the back, even if the PCB costs more.
  3. Naay. You could, for all I care, have it installed once, fully inside. Much like a cheap huge internal flash. Make it accessable through USB connection and/or a built in FTP/HTTP server only.
  4. Hmmm. Well I would have ...
Image

And the Junior for internal 8k etc. Also smaller with the same size as the Character ROM package. A bit more compatible with different mainboards.

Image Image
Last edited by TLovskog on Thu Dec 19, 2013 4:14 pm, edited 2 times in total.
BR
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Post by SkydivinGirl »

I don't mind the microSD format at all. I would just ask that it be accessible in some way, either through removal in a hard to reach location or through a standard USB connection that makes it show up on my PC. :)

By the way, I love your pool! I just put one in this year but didn't get to use it much because it was finished late in the summer. I'd love to see a picture of the finished project. Due to cost restraints, I went with a liner but I really like the concrete and tile that you are using. :wink:

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TLovskog
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Post by TLovskog »

Thanks for the feedback and the kind words of the pool.

My family REALLY wants it finished next summer ...
BR
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Post by joshuadenmark »

I'll go for number 1. or 3.

Cool design 8)
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Post by Mike »

So, one year after my last post in this thread, how's the progress?

I was somehow disappointed that, IMO, the project went into a mix of hibernation and creepy featurism instead of producing a working prototype that could also be tested by other people. :?

For me, the most interesting aspects were the RAM-link like feature for a really fast access to SD cards and a flexible RAM expansion/banking scheme. The other parts, like the WiFi module and OLED display, etc., were of minor interest to me. After all, what's the point in reducing the VIC-20 to a terminal to the main computer buried in the GCart?

I'd love to see this project continued.

Greetings,

Michael
Last edited by Mike on Sun Aug 31, 2014 1:17 pm, edited 1 time in total.
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TLovskog
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Post by TLovskog »

Mike wrote:So, one year after my last post in this thread, how's the progress?

I was somehow disappointed that, IMO, the project went into a mix of hibernation and creepy featurism instead of producing a working prototype that could also be tested by other people. :?
Sorry about that. My default life just got in the way with both my day time work, my work as a local politician and me and 2 friends starting our own business within Home Automation. There simply has been extremely little time left.

Also, I must admit that feature creep is one of my favorite sports ... In real life everything has to be good enough, delivered on time, cost effective, ... at home I can go at it without such concerns.

However, I haven't given up on this, and now and then I spend time on it. On the other hand, I feelt there is no need for an update with only new screenshots from the CAD systems.
For me, the most interesting aspects were the RAM-link like feature for a really fast access to SD cards and a flexible RAM extension/banking scheme. The other parts, like the WiFi module and OLED display, etc., were of minor interest to me.
Well the OLED display I have made optional and could be worked on later. Bluetooth, the optional cable for IEC and the MIDI interface is perhaps a bit exaggerated. When it comes to WiFi I would personally really like to be able to LOAD/SAVE to/from a server.

The hardware has now been designed with gradual upgrade in mind. The thought is to be able to deliver a hardware that has the basic features, but are done as programmable as can be expected, for future upgrades with more and more hardware features enabled.
After all, what's the point in reducing the VIC-20 to a terminal to the main computer buried in the GCart?
Totally agrees, and that has not really been my thought. Although with today technologies it is very hard to not create an add-on with much more power than the VIC 20.
I'd love to see this project continued.
Thanks for that. That is very inspiring.
BR
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Post by Mike »

TLovskog wrote:However, I haven't given up on this, and now and then I spend time on it.
Well then, I also have my share on unfinished projects on the VIC-20. ;)

Of course there's no fixed deadline for hobbyist projects (unless there's something like a demo-party and you want to attend a compo with the result of your project) - but then, to quote us both from two earlier posts:
Mike wrote:I'll keep an eye on your project, let's see what results. :)
TLovskog wrote:Auch again. The idea with going public with projects is to have a little pressure to put some action to the words.
That said. This is a hobby project with a tight budget and very loose time plan.
;)
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Re: My hardware project :: GCart 2011

Post by Topiux »

Hi Thomas,

Time for a "before the end-of-the-year" checkup?

BTW, how did the pool came up? lots of summer fun I guess...

Topo
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