STE V1.5 32MHz BOOSTER - STATUS

Help & information about the STE V1 booster.
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exxos
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by exxos » Fri Nov 09, 2018 2:08 pm

Right, it is pretty conclusive now that the ROM simply cannot run faster than effectively 32MHz. But the main problem here is the decoding speed by the ST chipset for the ROM chip enable line.. So nothing I can do about that.

So by default the ROM access will have to have a wait state inserted. I will however see if I can tweak the firmware so this can be turned off, some people may get lucky and it may be stable for them.. But obviously I'm going to have to program these with a wait state as the default. I will try to do this with a jumper wire on the back of the GAL... For example wired to 5V is wait states enable, and wired to 0V is wait states disabled.

Once I have created the new firmware (assuming it can be done) I will revisit the 40MHz on this current board...
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
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JezC
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by JezC » Fri Nov 09, 2018 2:26 pm

exxos wrote:
Fri Nov 09, 2018 2:08 pm
Right, it is pretty conclusive now that the ROM simply cannot run faster than effectively 32MHz. But the main problem here is the decoding speed by the ST chipset for the ROM chip enable line.. So nothing I can do about that.

So by default the ROM access will have to have a wait state inserted. I will however see if I can tweak the firmware so this can be turned off, some people may get lucky and it may be stable for them.. But obviously I'm going to have to program these with a wait state as the default. I will try to do this with a jumper wire on the back of the GAL... For example wired to 5V is wait states enable, and wired to 0V is wait states disabled.

Once I have created the new firmware (assuming it can be done) I will revisit the 40MHz on this current board...
Would this be another area where a future FPGA-based solution could overcome the limitation of the original chipsets? Not much help right now, but if we have a list of potential improvements to go on the future upgrades then it's all up for discussion.

Also, did I see another post where you considered loading the ROM into fast SRAM to get around some of these limitation?
Or has my brain switched off for the weekend? :lol: :roll:

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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by exxos » Fri Nov 09, 2018 2:32 pm

JezC wrote:
Fri Nov 09, 2018 2:26 pm
Would this be another area where a future FPGA-based solution could overcome the limitation of the original chipsets? Not much help right now, but if we have a list of potential improvements to go on the future upgrades then it's all up for discussion.
If it had its own PLD to do the decoding then it would save something like 10ns... But that isn't something I am going to do with this booster, it would otherwise make the simple design larger and more complicated to gain a few extra MHz... Plus I am not doing any more STE boosters after this one anyway. viewtopic.php?f=20&t=1182

JezC wrote:
Fri Nov 09, 2018 2:26 pm
Also, did I see another post where you considered loading the ROM into fast SRAM to get around some of these limitation?
Or has my brain switched off for the weekend? :lol: :roll:
That was probably in the next gen booster (SEC BOOSTER) where I actually have the same problem that ROM isn't fast enough... So I was considering copying ROM into its own fast RAM block on power up... So all ROM access is done from the fast ram not the actual ROM chip itself.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by JezC » Fri Nov 09, 2018 2:41 pm

exxos wrote:
Fri Nov 09, 2018 2:32 pm
If it had its own PLD to do the decoding then it would save something like 10ns... But that isn't something I am going to do with this booster, it would otherwise make the simple design larger and more complicated to gain a few extra MHz... Plus I am not doing any more STE boosters after this one anyway. viewtopic.php?f=20&t=1182
Yes, I'm fully aware of (and understand) the extra problems with STE/Falcon etc. - just keen to try & help if/when I can to help get the STF remake & successors up to a point to exceed their performance.
exxos wrote:
Fri Nov 09, 2018 2:32 pm
That was probably in the next gen booster (SEC BOOSTER) where I actually have the same problem that ROM isn't fast enough... So I was considering copying ROM into its own fast RAM block on power up... So all ROM access is done from the fast ram not the actual ROM chip itself.
Sounds like I'd remembered at least some of it correctly then...I'm guessing that the future booster plug-ins for STF remake etc. will be faster CPU with fast memories on-board for the s/w that can use it.

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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by exxos » Fri Nov 09, 2018 2:46 pm

JezC wrote:
Fri Nov 09, 2018 2:41 pm
Sounds like I'd remembered at least some of it correctly then...I'm guessing that the future booster plug-ins for STF remake etc. will be faster CPU with fast memories on-board for the s/w that can use it.
The SEC booster is being prototyped on the STFM, so there will be boosters for that machine... It will take over from the V2.2 booster.. it will also double up for the STF remake booster. The next STF board will have a DIP CPU socket to insert boosters made for the STFM.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by JezC » Fri Nov 09, 2018 3:03 pm

:thumbup:

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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by exxos » Fri Nov 09, 2018 3:28 pm

36MHz WITH WAIT STATES

0WS_result.png
0WS_result.png (185.31 KiB) Viewed 52 times


36MHZ WITHOUT WAITSTATES

NOWS_result.png
NOWS_result.png (185.56 KiB) Viewed 52 times


And just for the sake of comparison with the previous V1 32MHz booster

ste32mhz.jpg
ste32mhz.jpg (125.03 KiB) Viewed 52 times

So basically 36MHz current booster with waitstes on is the same speed as the previous 32MHz booster... With the exception that integer division is now at 401% from 355%. The CPU scores are showing lower because of the lower ROM access speed. Overall this makes no odds as it is still effectively a 32MHz booster.

Without the wait states we have a small boost in speed in most of the tests.. But as said before, it will be very hit and miss if any machines will run in this mode.


Now onto re-trying the 40Mhz osc with waitstates enabled...
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by exxos » Fri Nov 09, 2018 3:49 pm

This is 40MHz with wait states

40WS_result.png
40WS_result.png (184.86 KiB) Viewed 47 times


just for comparison again the 36MHz....

0WS_result.png
0WS_result.png (185.31 KiB) Viewed 47 times

ROM Access has tripped over to 309% again... So I'm hoping the ROM will can okay still... But of course this is also pushing the CPU again now..

Will post back how many loops it managed to do before crashing later... :)

Though I really do hope that it will sustain 40MHz... But that still just means that this particular booster will run at that speed, it does not mean that all the CPUs will run at 40MHz....
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

troed
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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by troed » Fri Nov 09, 2018 3:51 pm

I'm confused by the much higher aggregate CPU result (254%) for the 32MHz one compared to 38 or even 40MHz without waitstates.

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Re: STE V1.5 32MHz BOOSTER - STATUS

Post by JezC » Fri Nov 09, 2018 3:56 pm

troed wrote:
Fri Nov 09, 2018 3:51 pm
I'm confused by the much higher aggregate CPU result (254%) for the 32MHz one compared to 38 or even 40MHz without waitstates.
Yes - looks like all the individual cpu scores are higher but the overall cpu is lower...bizarre :?

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