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Post by eslapion on Jun 24, 2019 20:09:21 GMT
I am now offering a new type of 64k RAM expansion for the VDC. The traditional type of 64k expansion board for the VDC simply disconnects the two 16k x 4 DRAM chips from the mainboard and offers a pair of sockets for two 64k x 4 DRAM chips. This new type is much smaller, consumes much less power and uses a single static RAM chip. Here is a picture of the board of the product: C128 VDC 64k expansion PCB The price tag is 15$US or 13.50 Euros per unit + shipping.Shipping a small packet (up to 8 units) to the US is 8$. Shipping cost for Australia/NZ and South America is 10$US, Europe is 8 Euros. Quantity discounts are applicable.
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Post by eslapion on Jun 24, 2019 12:09:17 GMT
For one thing you should NEVER use a 65C22 or R65C22 on ANY 8 bit Commodore computer. That's because these chips IRQB output is totem pole instead of open collector/open drain output as real MOS 6522 chips are.
For another, a CORRECT replacement is the currently produced W65C22N (NOT W65C22S) which you can order from Mouser - it is made by WDC, the Western Design Center. You can safely use these in the VIC-1540, 1541, 1571 disk drives and the good old VIC-20.
While the original MOS 6522 consumed about 60mA of power, Western Design Center's VIA consumes about 3mA when used at 1-2MHz as it is in Commodore 8 bit computers and drives.
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Post by eslapion on Jun 10, 2019 15:01:28 GMT
After running this code I get A=2.00041079;T=34; What are you trying to show? The pokes will turn off the display then activate the 2MHz mode even if you're in C64 mode. This should give you a C64 which runs at twice the speed when the display is disabled. Compare to: T=34 is indeed faster than 73... even faster than the C128 in fast mode with 41.
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Post by eslapion on Jun 10, 2019 14:52:32 GMT
300 units sold!
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Post by eslapion on Mar 23, 2018 9:59:11 GMT
200 units sold!
and now, say hello to LumaTOLB, the functionality of LumaFix and TOLB combined in a single board!
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Post by eslapion on Dec 15, 2017 21:57:32 GMT
150 units sold!PLAnkton, GandALF and TOLB are now distributed in Europe by Poly Play. www.polyplay.xyz/Capture of TOLB NTSC outputs (click to enlarge) TOLB NTSC Color clock and dot clock outputs. The small error in frequency output is caused by the oscilloscope aliasing. Exact frequencies are 14.31818MHz for color clock and 8.18182MHz for dot clock respectively.Capture of TOLB PAL outputs (click to enlarge) TOLB PAL Color clock and dot clock outputs. The small error in frequency output is caused by the oscilloscope aliasing. Exact frequencies are 17.7344MHz for color clock and 7.882MHz for dot clock respectively.
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Post by eslapion on Nov 13, 2017 21:31:26 GMT
I have several C128s; should I consider changing the 8701s to TOLBs? How do I know if they are a problem? I have on a few occasions tweaked the trim capacitor with a frequency counter using pin 8 of the 8701 to get as close as possible to 14.31818 MHz, but other than that, I had never thought very much about the 8701 until I read this topic. Would a TOLB help a finicky RAMLink cartridge? Most people who buy TOLB use it to convert C64 and C128 between PAL and NTSC but it obviously can make a good substitute for the 7701/8701 if yours has failed or you want to do away with the need to adjust the trim capacitor. TOLB has a built-in SMT oscillator and is therefore always providing the very exact frequency required. No, TOLB will not change anything about a problematic RAMLink.
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Post by eslapion on Nov 4, 2017 0:55:45 GMT
120 units sold!
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Post by eslapion on Aug 8, 2017 1:22:40 GMT
100 units sold!
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Post by eslapion on May 29, 2017 8:49:07 GMT
Special offer!
Buy one or more TOLB and get a 10% discount on up to 5 PLAnkton modules - you also save on shipping when you combine orders.
60 units sold!
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