V2.5 BOOSTER CURRENT PROTOTYPE STATUS (SEC BOOSTER)

[exxos]

Got my boards back

Probably be another month before I can invest some time into them though

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[Icky]

Nice! Looking good.

[exxos]

Currently just verifying my new MB setup works With the previous SEC booster...

So took a screenshot of the current scores...

The image below is referenced against a machine with the blitter enabled, it was more out of curiosity than anything.Of course, the RAM bottleneck is why the listing test is only 55%. But in most other tests, 50MHz can actually outperform a stock blitter...

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And referenced against a normal stock STFM..

IMG_4332.JPG (104.94 KiB) Viewed 438 times

Next I need to find a new blitter, as I think a pin got bent and killed it on this board


EDIT:

With blitter ON..

IMG_4333.JPG (106.04 KiB) Viewed 431 times

EDIT2:

I think something is going screwy relating to the wakeup states again Sometimes I can turn the ST on, and it will load GB6 absolutely fine, and then other times when I power up, it keep saying it cannot read the floppy..

I am not really sure why this would matter, as the 8 MHz clock shifting in phase, would not matter as the booster would sync to that clock anyway... So it looks like yet another screwy problem to diagnose

[exxos]

So far not having much luck I found I missed a resistor off A1.. basically thats the only difference between this booster and the previous one.. I routed A1 via the PLD... But I have bypassed the PLD and hardwired it, with the same code as worked in the previous SEC, and doesn't even try to boot

I am currently continuity checked on the board, but so far haven't found anything wrong. The CPUs were left over from batch I got which was used on the previous boards, so I do not expect them to be faulty, although I have tried to board so far and both of them are completely dead..

Superduper built up my original boards, my normal assembly place built up these current boards. So may send of these boards to superduper to build if I can't get anywhere. Currently I am assuming it's some assembly problem, but as yet I cannot find anything wrong

[exxos]

Now booting.

I routed BERR via the PLD (no idea why) but I didn't code the connection

#bobslaw
#dumbass

[PhilC]

Was there alcohol involved?

Let me know if you need a second tester.

[exxos]

Will do, Need to solve this odd floppy problem yet tho It was intermittent on the previous board, this one always seems to act up, could be a fluke though..

[exxos]

So I tried a 720K floppy and it booted right up.. so may just be some odd issue with the floppy itself (which would be typical) or something is going a bit unstable with the 1772 running 16MHz..

EDIT:

It seems the format a high-density disc time, so at this point I'm just going to assume it's a bad floppy

In any case, I do not seem to have any screwy DMA issues like I did on the previous board, but this could either be down to the fixes I have done in the code, or because it is a different motherboard.

[PhilC]

No more floppy problems

[exxos]

It was still acting up on reading floppies.... but it would work formatting and even booting from a 1.44 formatted as a 720k.. so I changed the 1772 and its behaving again now...

Its possible this could be a side effect of the 1772 & DMA "clash" which is why I re-designed the stuff on the remake boards, hence the 1772 buffer boards were created.