Shuriken

Please have a look at the 78xx datasheet at page 24 figure 13. As you can see there, the application of the transistor is not current limiting. If the current surpasses 1A the transistor will take over. This will increase the current output to a max of 3 to 5A depending on the transistor used. As i said the design is not short circuit protected. So i should adapt it to resemble figure 15. at page 24 of datasheet. My intention is to use 2 transformers. 1 for 5V and 1 for 9/12V line. The 5volt line is most sensitive. Hence the more intricate SCR design. I intend to include a simpler (less sensitive) zener diode based scr design on the 9V/12V line.

This is what i have come up with so far: This design should be sufficient for 5A on 5V+ line. The TIP2955 is 15A. And the packaging is a bit bigger then the TIP31. I haven't really specced the thyristor yet, just picked one from Eagle lib. Edit: Meh, i need to add a short circuit protection as well.

Ok, well i am working on my schem atm. Now wondering if instead of just using a 78S05 it would be a good idea to combine it with a transistor something like a tip2955. That way it would have a little more room to breath. And better power dispensation. Also struggling to add the MC3423 to my eagle library. :pinch:

I am curious what you have come up with. So looking forward to seeing your schem.

I think he means this one: If you adapt this to 2 separate windings then you need to add the diodes again. edit by nILS: Added a link to the picture's source ;) This design is from the wiki, where you can find some explanation as well. Sadly I ran outta time to brush up the other designs as well. It's back on my ToDo list now.

Someone correct me if i am wrong. But incase of a latchup. The parasitic structure (eq to thyristor) can change the polarity. So the GND is changed to a -DC and the +DC is changed to GND. For the other diode have a look at this datasheet and scroll to page 11.

As i said, i have to look into a crowbar design. So that's not included into the current schematic. So there is no OVP or OVC protection atm. Just protection for the regulator and for latchup.

The diodes around the regulators are there for protection of the regulator incase of input short. The diodes on the output are (old skool) there for the protection of the phenomenom called latchup. As the sid chips are old style CMOS chips they are vunerable to this. This design is much like Roland's design for the Juno 60. Which holds a lot of 4000 series cmos chips. When the C64 PSU fails the 5V regulator will put out something like 10V. Since you have 30 euro chips behind it, a 1 euro circuit can make the difference. So i figure you spend a few bucks to safe you from spending a lot of bucks makes sense. The crowbar circuit is there for when the regulator fails. If i look at the datasheet of the mc3423 it can also help with current limiting.

I am also still looking to build a psu. I made a preliminary design: The pic is kinda dated. As i wont be using a 78S09 but a 7809. Have to look into a crowbar design as well. It seems the zener option doesn't work so well as it might get trigger by a little peak at startup. The SCR option is better. It seems there are a couple of IC options out there. Someone pointed me towards the Motorola MC3423. However this seems to be no longer made. However i just noticed reichelt has it on stock still.

Ah, i didn't think of that. I was indeed hoping to use the buffer on the controller. I haven't hooked it up either. Might do on the weekend though.

It seems SPI is out of the question. As first of all jumper wise i can only choose 8 or 16 bit. And besides it looks like the sdcard uses the spi interface already.

Shipping to either nILS or me would be pretty much the same, as we are both based in Europe. Might be a good idea to wait a bit and see if there are any US based takers.

I wouldn't mind helping you out. But it wouldn't be that effective if i live on the other side of the globe. So what nILS said :ahappy:

I received mine as well. I knew about the sd-card. I wonder which way to hook it up is fastest: 8-bit,16-bit or SPI. Well, guess it's trail and error.

Can't wait....i am sure it will be a worthy replacement for my half finished MBFM.

It's probably more like the 8580 was in high demand. And supplies are pretty much running dry. So people turn to the 6581 now.

That's still only 1A. The 78S05 can do 2A. That would be the case if i had a 7809 inside the MB6582. I figured why put an additional heatsource inside the box?

As i am still in the process of making my own. I am curious to know what kind of Power Regulators you are planning to use? I was thinking of using 78S05 and 7809.

And i am sure you are wrong on the SIDs as well. If you check the Sammich build guide or http://www.ucapps.de/mbhp_sid.html the SIDS use both 9V and 5V or 12V and 5V. I am desinging my own psu aswell. Since people have problems with the C64 PSU i figured 1A on the 9V and 2A on the 5V would be on the safe side.

1.7 amps on the c64c(II) brick. But i will go for 2 amps.

http://www.elektron.se/products/octatrack?section=faq says 64GB max.

Ok, mine is on it's way aswell. Code examples are here: http://www.4shared.com/file/kevwi3bU/Digital_Picture_Frame.html and i got a chinese driver here: http://www.egochina.net.cn/e-shop/ebay/Datasheet/V320P243282WSI7TB-PCB.rar

Has anybody tried these type of displays? It's not terribly expensive. http://cgi.ebay.com/3-2-262k-TFT-240-320-Color-LCD-module-Touch-Pane-/120640315337?pt=LH_DefaultDomain_0&hash=item1c16b91fc9 They come with an ILI9320 controller which supposedly can use both 8/16 bit parellel or SPI inferface. It even comes with a STM32 driver. Not sure how bad the cpu usage is :whistle: Edit: Darn, probably should have posted this in Parts Questions :pinch:

I don't think there is a subject that someone couldn't write a book about. But i am not sure in this case it would make much sense. My feeling is you are basically asking for a "Midibox for Dummies" book. If there ever was such a book to be written. It would probably start with: The author assumes the reader has already read "Electronics for Dummies" and "MIDI for Dummies". To be able to build an "as-is" project you would need just that. All the other information is on www.ucapps.de and for more indepth info you can search in the forum.

No i haven't but was checking the basics as you didn't mention it in your ts.