Centurbo 1 evolution 3b -> CT60 booster

[foft]

Hey foft, if it's convenient for you could you take some photos of your board and highlight the bus resistors in question? It's just that this hasn't been highlighted or done by anyone else yet (for a falcon) and it'd be nice to have some visuals on the matter. Thx.

I was wondering that. I'll take some and post them tomorrow, just packing up tonight.

[mikro]

Btw I wouldn't take that CT60 version of booster as some 'golden standard', it's definitely one of the less reliable ones.

[foft]

Btw I wouldn't take that CT60 version of booster as some 'golden standard', it's definitely one of the less reliable ones.

Thanks. Which one would you say is the most reliable when used with the CT60/CT63?

[Steve]

Btw I wouldn't take that CT60 version of booster as some 'golden standard', it's definitely one of the less reliable ones.

Thanks. Which one would you say is the most reliable when used with the CT60/CT63?

I use a Phantom which works fine as long as you have a good clock patch. (with a ct60e)

[foft]

Hey foft, if it's convenient for you could you take some photos of your board and highlight the bus resistors in question? It's just that this hasn't been highlighted or done by anyone else yet (for a falcon) and it'd be nice to have some visuals on the matter. Thx.

I was wondering that. I'll take some and post them tomorrow, just packing up tonight.

I think I need to get the proper camera and take some pics in the day!

P7/P11: data pull-ups
P8/P13/P17: address pull-ups

Take care, pin 1 is not always on the same side.

Falcon_bus_pullups.jpg (408.82 KiB) Viewed 2022 times

I should also note that this is for the main system address and data bus. The memory has its own address and data bus. I'll probably change the pull-ups there too and post another picture... Update: There aren't any I can see on the schematic, so they'd have to be added on the memory card I guess if it helps.

Also I want to check on the scope that it helps for the main bus.

[foft]

I use a Phantom which works fine as long as you have a good clock patch. (with a ct60e)

Thanks. I guess they are no longer made? Are the design files online somewhere?

[Steve]

@foft I bought mine from Tuxie of the Thunderstorm team. I think his email was thunderstorm@tuxie.de. I think he has some left from the last time we spoke.

[foft]

I found the fix for the CT63 booster. There is a patch wire on the bottom of the CT60, from pin 9 for the connector DTKCMB to one of the pins on the CT6x expansion port. I connected that up and ... now it lives in boosted mode I thought it was odd to have that wire soldered to U63 when it didn't go anywhere on the schematic!

ct60_patch_wire.JPG (463.7 KiB) Viewed 2066 times

So far Rodolph's clock patch seems stable, F030TEST.PRG gives me nice green bars in all modes. Though it doesn't work without the blitter, white screen when I'm using NVDI.

BTW does FPUtest work for those people using 95-100MHz? My rev6 is stable at 100MHz, but the FPU stops working properly at >94MHz.

[Steve]

@foft You'd be reaching the maximum possible speed of the CPU and FPU, so it is expected you'd start to get errors. Personally I wouldn't run my 060 that fast, it's not worth it in my opinion, the possibility of breaking the cpu is worrying. I run mine at 77Mhz and it's smooth as butter at these speeds.

[markus0321]

BTW does FPUtest work for those people using 95-100MHz? My rev6 is stable at 100MHz, but the FPU stops working properly at >94MHz.

This is normal, most rev6 shows FPU errors above 93MHz, sometimes it helps to raise the voltage on the processor from 3.3V to 3.8V, but this cannot be done on CT60/63 (power circuit common with CPLD and CPLD overheat above 3.5...3.6 V)
Edit.
68060 from the Freescale stable are even weaker, the FPU can miscalculate sometimes even at 85MHz..
I checked several pieces...