Logic families
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Good luck giving your MD a über OC
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
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Thanks, I wont be easy becuase my Vcc is around 3.6 Volt, I think it limits the overclockability (!?) of the cpu...
The YM2612 and the MB3514 are powered with 4.2V (anything lower the YM will produce wierd noises)
[OFFtopic]
I did it because my VDP is an ass, it's very hot @5V so I reduced to the minimum possible, (at 3.3V there is some tile corruption and locks)
And the 3.6 voltage makes possible connecting to new devices that only support LVTTL, cool eh?
[/OFFtopic]
The YM2612 and the MB3514 are powered with 4.2V (anything lower the YM will produce wierd noises)
[OFFtopic]
I did it because my VDP is an ass, it's very hot @5V so I reduced to the minimum possible, (at 3.3V there is some tile corruption and locks)
And the 3.6 voltage makes possible connecting to new devices that only support LVTTL, cool eh?
[/OFFtopic]
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My MD1 clone went pretty hot... I put heatsinks on the chips... my MD2 does get only warm...
I had to increase my DCs SH-4 vcore to overclock it... and I guess your 3.6volts will be a problem...
I had to increase my DCs SH-4 vcore to overclock it... and I guess your 3.6volts will be a problem...
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
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Well for now it isn't a problem after all and it is running perfectly @ 13MHz, the dotclock...
No graphic glitches, no locks, always sound, so I guess I can push even further hehe..
I am targetting for the highest frequency I can get, while maintaning everything perfect (like it is now).
Probably I won't overclock to an extent of seeing crap on the screen and/or locks every other second...
No graphic glitches, no locks, always sound, so I guess I can push even further hehe..
I am targetting for the highest frequency I can get, while maintaning everything perfect (like it is now).
Probably I won't overclock to an extent of seeing crap on the screen and/or locks every other second...
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Well, around 16MHz you'll probably get some issues.... my MD2 VDP goes crazy if the clock is above 14MHz, 10MHz is the most stable...
You may find this interesting : http://epicgaming.us/?p=4
You may find this interesting : http://epicgaming.us/?p=4
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
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Wow there are some insane clockings: 25~29MHz!, umm I'm expecting my MD to work flawlessly with a clock of around 16MHz(like you said), but I don't have many crystals... I do have a 16 MHz one though
Best shot would be building a variable frequency oscillator with a varicap diode, but I only have a concept idea, never tried to mount it, I dont even know exactly how to make the circuit... (simulating one at the moment)
What I'm planning to do is building the variable osc, test the ultimate stable frequency, get a crystal can closer but lower to that frequency, mount the oscillator with that 74AC00...
Best shot would be building a variable frequency oscillator with a varicap diode, but I only have a concept idea, never tried to mount it, I dont even know exactly how to make the circuit... (simulating one at the moment)
What I'm planning to do is building the variable osc, test the ultimate stable frequency, get a crystal can closer but lower to that frequency, mount the oscillator with that 74AC00...
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You might look at these. The ST1507 or ST1517 would probably suit you, depending on the frequency range you need.
http://www.pericom.com/products/timing/ ... s/vcxo.php
http://www.pericom.com/products/timing/ ... s/vcxo.php
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