exxos's Atari, Amiga & retro forum

Right i spent a good bit of yesterday on the firmware... I've been removing the clock switch trick and dealing with the resulting things that have popped up.

I had an issue with IACK not working until i realised I'd set the 060 to ignore the TA for 2 clocks. I changed that to 1 and its fine and faster.

I had an issue with lockups in the slave state machine.. thats been resolved.

I got the firmware from floppy and started looking at chipram performance. I've managed to get some gains here.. Basically the Amiga is pretty crap.. if your cycles have a gap between them it doesnt respond in a timely way... I started with
I trimmed off a bit of fat at the start of the cycle and got to this...
You can see most of the time is spent waiting for the Amiga... ROM cycles are pretty good but Chipram slot allocation is nasty. If you go over the slot time it seems your bandwidth will half because you missed where the amiga wants you to start a slot. Now i need to get a little bit more off the tail end of the cycle and we're good.

Final thing to deal with is the fastmem <-> chip transition.. I get a lockup at the moment. I know why i just need inspiration to solve it.

terriblefire wrote: 24 Jul 2021 15:54 Just want to put a final thing in here for those kicking off on EAB/Facebook and PPA.PL...

I really get frustrated when people are getting pushy with vendors (software and hardware alike), I completely walked away from most things Atari ST/Amiga on Facebook, was always turned off by the old hags on EAB, and PPA.PL, isn't really in my native language (and I've heard enough to avoid entirely anyway)

I've found here (Exxos), some of the discord channels (especially AmigaBill's) excellent refuges from those places, have frequented only these two for almost a year now, and haven't looked back since.

I'm sure your new firmware will be fantastic, my TF1260 is extremely useful as-is anyway, so I view any subsequent release as a nice bonus.

One 14Mhz cycle per dtack trimmed...

Nice work, looking good mate! Take your time, I’m in no hurry to send my card away for a firmware update just yet, I’m enjoying it as is. :D

I've just got some numbers for the chipram improvements i've been working on ...
Its not stellar yet and right now burst mode is off for fastram.. but its moving in the right direction.

Thanks for the updates, it’s looking good :)

thanks for keeping us in the loop big man :)

Question, are these improvements keeping your clever drop down to 14Mhz for cooling when accessing Chipram or is that lost?
And then if lost, was the main heat gains just on CPU? Or on CPLDs also ?
I know heat generated by chips is all relative and not necessarily detrimental. I'm surprised how hot a Raspberry Pi runs.

I'm removing the 14Mhz trick.. It was expressed by democoders that they do FPU stuff during the chipram accesses and slowing the clock hurts that.

Its pretty much a firmware rewrite at this point.

burst is back on