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PostPosted: Sun Mar 22, 2009 4:16 pm 
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Joined: Thu Feb 05, 2009 4:04 pm
Posts: 18
Here you are.... I even pulled of the EPROM to let you have a view what's behind it ;)

Image

Image

Image


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PostPosted: Wed Mar 25, 2009 6:48 am 
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Joined: Thu Mar 12, 2009 12:41 pm
Posts: 10
Location: MELBOURNE, AUSTRALIA
:D Thanks SHADOWFAX for the help, I have designed the printed circuit board allready.
:D Its about 1/3 rd smaller the the original. 8)
I just need to do the schematic diagram now. :)

B.B.

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IT'S NOT SPEED THAT KILL'S.
IT'S THE SUDDEN STOP!!!


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PostPosted: Thu Mar 26, 2009 4:00 pm 
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Joined: Thu Mar 12, 2009 12:41 pm
Posts: 10
Location: MELBOURNE, AUSTRALIA
THIS WAS UPDATED ON MAY 18TH 2009, I FOUND I FORGOT TO ADD THE 2K7 RESISTOR TO THE SCHEMATIC.

HERE IS MY PCB I HAVE DESIGNED, ITS SMALLER THAN THE ORIGINAL.

PARTS LIST:
-----------------------------------------------------------------------------------------------------------------------
1 * 2764 EPROM - PROGRAMED WITH THE FASTLOAD.BIN FILE, NOT THE .CRT FILE.
1 * 7407 HEX BUFFER WITH HIGH VOLTAGE OPEN COLLECTOR OUTPUTS.
1 * 2K7 .25WATT RESISTOR.
1 * 0.47MF MONOLYTHIC CAPACITOR ( LEFT SIDE OF BOARD ).
1 * 0.1MF MONOLYTHIC CAPACITOR ( TOP, BETWEEN THE TWO CHIPS ), FOR SPIKE SURPRESSION.
-----------------------------------------------------------------------------------------------------------------------

CLICK ON THE ATTACHMENT BELOW TO DOWN LOAD EVERYTHING. :D
THIS WAS UPDATED ON MAY 18TH 2009, I FOUND I FORGOT TO ADD THE 2K7 RESISTOR TO THE SCHEMATIC.

:mrgreen: I HOPE YOU ALL LIKE THE WORK I PUT INTO IT OVER THE LAST FEW DAYS OR SO.. :mrgreen:
DROP ME A MESSAGE OF WHAT YOU THINK, OR ENQUIRIES.
B.B. :D


Attachments:
File comment: Added file for preservation //RaveGuru
fastload_update.zip [1.25 MiB]
Downloaded 901 times

_________________
IT'S NOT SPEED THAT KILL'S.
IT'S THE SUDDEN STOP!!!


Last edited by bitblaster66 on Mon Oct 11, 2010 10:22 am, edited 4 times in total.
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PostPosted: Sat Mar 28, 2009 8:45 am 
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Joined: Thu Feb 05, 2009 4:04 pm
Posts: 18
Thank you too. This will helps others.


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PostPosted: Thu Apr 02, 2009 2:23 pm 
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Joined: Wed Jan 11, 2006 12:22 pm
Posts: 866
Looking very neat indead! Good job!! :D


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PostPosted: Tue May 05, 2009 11:30 pm 
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Joined: Thu Dec 27, 2007 7:05 pm
Posts: 30
Location: The Netherlands
What is the time constant that the pull-up and the C implements?

What is in the C64? Let's say 3.9kOhm.. 470nF with 3k9.. If these are the values, tau is 1.8 ms. TTL trip points are as low as 0.8V, which is roughly 0.16x5V, thus only 0.17 tau (-ln 1-0.16). => 320µs. So if the cart hasn't been accessed every 320µs, either on ROML, IO1 or IO2, then it disappears. That seems to be quite a small value. However, because the cart is always visible on IO2, which resets the C, even this small value could be sufficient.

I'll implement the Epyx emulation in the 1541Ultimate with 512 PHI2 cycles delay. I am sure that would do.

/Gideon


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