CURRENT PROTOTYPE STATUS (SEC 64MHz 68000)

[exxos]

Finally found the updated PCBs. I will try and build one up to test soon. I was planning to get 5 made up to test but the assembly place is kinda shut currently :( so I'm having to build stuff myself which is no fun at all. I cant test the SRAM boards until the new sec boards are built.

[exxos]

So I have actually had the latest PCBs for a while.. But with so many projects constantly ongoing it is hard to find time to work on this these days :roll:

I need to build one of these up as this has the I/O port for the fast ram boards is shown a couple posts up..

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As shown in my blog earlier, I just hooked up a previous version to make sure it was all working fine before starting a new build... The new build had some pins rearranged and of course the 4 SRAM IC outputs... Basically I should be able to get like 64MHz into fast-ram. I really want to see what the proper results are for this speed on a basic 68000 CPU..

One reason for the delays in this project was because the SRAM chips were incredibly expensive and the board would cost around £120 just to make... This is the reason I started a new topic about porting the SDRAM controller from the TF330 to a new board, as it would be a lot cheaper to produce that way.. So I hope to make the fast ram as fast as possible, in the order of like 10ns, and make the board at a more sensible price. So while the booster has been around for a while, it could not really progress until the faster RAM board is completed..

In any case, I do have several of the original boards which are still untested, but I think when I build up hopefully the final SEC booster version I actually still working with one of these current fast ram boards... 64MHz speeds should be easily possible with this current setup.

[exxos]

I guess I should have found the bits before pasting the board :lol: :roll:

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[rpineau]

:lolbig:
I did exactly that last week. Fully pasted a board, starting installing all the main component, moved to the caps and resistor to realized I was missing a bunch !!!

[exxos]

I did exactly that last week. Fully pasted a board, starting installing all the main component, moved to the caps and resistor to realized I was missing a bunch !!!

:lolbig: :bravo: :imwithstupid:

[exxos]

So the first annoyance with this...

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[exxos]

2nd attempt... I pushed the IC flat down on the desk to level the pins this time... I need to beep it all out next.. probably next one I do I probably print a bit more paste on the PCB..

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EDIT:
Everything beeps out :)

Need to find a PLD to solder on the bottom now.. think I might be out of them :roll:

[exxos]

So no PLD's... So your sacrifice is not in vain earlier version :2k2:

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IMG_6122.JPG

[exxos]

Pasting away..

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EDIT:

Talk about inconsistencies to what is actually pin one :roll:

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This one (soldered down one) seems to be small dot is pin 1 , with the corner cut off more..

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Assuming the small dot on the new chip, no corners are cut.. but then why have a BIG dot on the chip ? Does that mean its pin 1 or the smaller dot ?! All the corners look the same to me on this one...

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I will have to assume the text is correct orientation and the smaller dot is still pin 1..

[exxos]

Anywhos, time for a bath with the board now..

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EDIT:

All clean :)

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