Welcome, Guest. Please login or register.

Author Topic: Prelude 1200 - heavy distortion (and crash) above 27420Hz  (Read 3965 times)

Description:

0 Members and 1 Guest are viewing this topic.

Offline Dwyloc

  • Full Member
  • ***
  • Join Date: Apr 2005
  • Posts: 208
    • Show all replies
Re: Prelude 1200 - heavy distortion (and crash) above 27420Hz
« on: August 15, 2014, 10:17:19 AM »
Quote from: rvo_nl;770916
Hi, took me a few hours, but Ive got the machine running with just 2Mb. When I run a digibooster mod over AHI, there is no distortion. It doesnt matter if the clockport extension cable is connected or not. I was quite surprised by this. The only thing I have removed is the ppc + bvision. Any ideas?

Edit: With PPC+Bvision+256Mb connected, I stil boot into the same Workbench installation I am using now. In that situation, the output will crash the system.


@rvo_nl
This is just a whiled guess but it sounds like some sort of timing problem.

So the first think I would try with the BlizzardPPC reconnected is to go into its own early startup menu.

I don't have access to my BlizzardPPC at the moment to check what key combination you hold down on reboot to get into the menu BlizzardPPC setting menu.

But it allows you to change the ram speed and make play with some other performance options related to the context switching between CPU's if I remember correctly.

So I would make a note of the current settings then try changing them one at a time help.

Its also possible that that its one of your RTG setting causing the issue so you could try without the blizzardvisionPPC monitor driver loaded and any other libraries moved out the way to stop them loading if you have not already tried that.

Anyway good luck and I am now wishing I had time and space to get my A1200 Tower out of storage and refit my BlizzardPPC and BlizzardVision instead of using my mediatorSX and Blizzard040 cards that are currently fitted to it.

I just don't have the space to have it setup at the same time as my Sam440, PC and minimig :-)
Sam440ep 667mhz 512megs OS4.1
Minimig, 4MB RAM, ARM add-on board
Amiga 1200 Eyetech mk4 Tower, Blizzard 1240 040/40 32MB Fast ram, IDEFix Express mk2, mediatorSX pci, Voodoo3 PCI, PCI network card, OS3.9 BB2.
 

Offline Dwyloc

  • Full Member
  • ***
  • Join Date: Apr 2005
  • Posts: 208
    • Show all replies
Re: Prelude 1200 - heavy distortion (and crash) above 27420Hz
« Reply #1 on: August 15, 2014, 02:29:05 PM »
I guess that leaves trying with a different revision of A1200 motherboard or timing fixes to your existing board other than that I am out of ideas sadly :-(
Sam440ep 667mhz 512megs OS4.1
Minimig, 4MB RAM, ARM add-on board
Amiga 1200 Eyetech mk4 Tower, Blizzard 1240 040/40 32MB Fast ram, IDEFix Express mk2, mediatorSX pci, Voodoo3 PCI, PCI network card, OS3.9 BB2.