DMA port "update" ideas..

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exxos
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Re: DMA port "update" ideas..

Post by exxos »

ah :roll:

Never really thought about the DMA socket, is more concentrating on getting it made on just two layers keep board cost low...

I guess it will have to be stacked in a couple of sockets to pad out the gap..
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Re: DMA port "update" ideas..

Post by Icky »

exxos wrote: Thu Nov 08, 2018 8:49 pm ah :roll:

Never really thought about the DMA socket, is more concentrating on getting it made on just two layers keep board cost low...

I guess it will have to be stacked in a couple of sockets to pad out the gap..
Damn I ran out of sockets to stack :( It only needs one more as the ACSI cable plug housing is higher than the actual socket.

I feel a soldering improv coming on.

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Re: DMA port "update" ideas..

Post by Icky »

So first off - always check the components before you put them on your board. Never assume that what comes in a package is what you expect :)

The chip I plugged in was a LS244 now that was never going to work. Found an LS245 in my stash of LS' and bingo it is working.

One other thing to mention you have to stack it high enough to get some sort of insulator under the board as it will short on the ACSI connector shielding.

Have been copying files between Floppy and Gigafile fine.

It does fit in nicely next to the Floppy un-f*ck board. You could have one Un-f*ck board to rule them all if you combined them into one.

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Re: DMA port "update" ideas..

Post by exxos »

ah crap I put 244's in the kits didn't I ?!

great to know its working though !
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Re: DMA port "update" ideas..

Post by Icky »

exxos wrote: Thu Nov 08, 2018 10:23 pm ah crap I put 244's in the kits didn't I ?!

great to know its working though !
Not to worry - got there in the end :)

Looking at my LS stash I seem to have a lot of LS244's and LS245's floating around so I was lucky.

Yes - great its working feel a lot better using Gigafile and Floppy together to transfer now.

I don't want to go through that NASTY DMA / BAD 1772 debacle again.
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Re: DMA port "update" ideas..

Post by exxos »

Icky wrote: Thu Nov 08, 2018 10:27 pm Not to worry - got there in the end :)
:blonde:
Icky wrote: Thu Nov 08, 2018 10:27 pm Yes - great its working feel a lot better using Gigafile and Floppy together to transfer now.

I don't want to go through that NASTY DMA / BAD 1772 debacle again.
:bravo:

I guess it would be interesting to try this on a STE which is having DMA issues... *writes on 2020 to do list* :lol:
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Re: DMA port "update" ideas..

Post by Icky »

exxos wrote: Thu Nov 08, 2018 10:33 pm I guess it would be interesting to try this on a STE which is having DMA issues... *writes on 2020 to do list* :lol:
2020 - Thats optimistic :D

On to the reset board now but am still waiting on the TL7705 to arrive.
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Re: DMA port "update" ideas..

Post by exxos »

Icky wrote: Thu Nov 08, 2018 10:27 pm I don't want to go through that NASTY DMA / BAD 1772 debacle again.
Now the 1772 board is in place, it *might* be worth pushing 16MHz into the DMA again and see what happens...
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Re: DMA port "update" ideas..

Post by Icky »

exxos wrote: Tue Dec 11, 2018 5:41 pm
Icky wrote: Thu Nov 08, 2018 10:27 pm I don't want to go through that NASTY DMA / BAD 1772 debacle again.
Now the 1772 board is in place, it *might* be worth pushing 16MHz into the DMA again and see what happens...
Will look at this today. Is this worth a jumper on the Rev.H board to be able to select between 8MHz and 16MHz?
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Re: DMA port "update" ideas..

Post by PaulJ »

exxos wrote: Thu Nov 08, 2018 10:23 pm ah crap I put 244's in the kits didn't I ?!

great to know its working though !
You are one hell of a multi-tasker.. how do keep every strait?
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