maprom 1.8 working on TT

[Steve]

I just decided to try @agranlund 's maprom on my TT and it makes it marginally faster some slight decrease in vdi but overall faster. @tuxie

Gembench Vs itself before/after

PXL_20210223_162920020.jpg (566.05 KiB) Viewed 3674 times

[exxos]

I think maprom really needs fast alt-ram to give speeds boosts.

[czietz]

Is it any faster / different that what ROMSPEED would do on the TT?

https://seimet.de/atari/files/rmspd311.zip
https://github.com/uweseimet/atari_publ ... r/ROMSPEED

[Badwolf]

That's a bit strange. 2x speed on ROM access, but display routines are only just break even, some getting worse?

Is there something clever going on under the hood of TOS3 normally?

BW

[exxos]

That's a bit strange. 2x speed on ROM access, but display routines are only just break even, some getting worse?

Never noticed that.. maybe @Steve can try without caches on to see if it drops ?

[Steve]

Wow @czietz thanks for the tip, romspeed is amazing

PXL_20210223_181129272.jpg (442.33 KiB) Viewed 3646 times

[stephen_usher]

Remember that the ROM access on the TT normally is 32 bits wide, which speeds it up somewhat. The TT-RAM interface is faster than the ROM but also 32 bit, so it doesn't make as much difference as it would on an ST+TF, which changes slow+16bit (two read cycles) to fast+32bit (one read cycle).

[czietz]

EDIT: I see that I'm too late.

This is with ROMSPEED mentioned above - where the reference (=100%) is my TT running TOS from ROM:

IMG_4645.JPG (409.57 KiB) Viewed 3638 times

The absolute numbers are different from your TT because mine is accelerated to 48 MHz.

[Steve]

@czietz guys you gotta sort me out with a speedy already!

[Badwolf]

I had a go comparing the both on the Falcon @48MHz (speed relative to same configuration with hardware ROM).

As I expected, the results are pretty much the same.

MAPROM:

dfb1_maprom.jpeg (132.61 KiB) Viewed 3613 times

ROMSPEED:

dfb1_romspeed.jpeg (129.37 KiB) Viewed 3613 times

So does that imply MAPROM doesn't like the TT? (I have looked at the sources before, but it's all Greek to me )

BW