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Disable Radius SE '020 accelerator?

JC8080

Well-known member
Does anyone know of there is some of programmer switch procedure to disable a Mac SE Radius '020 accelerator on boot? My Floppy Emu doesn't work in HD mode with the accelerator, it would be nice to be able to disable the accelerator so I can copy from my Floppy Emu in HD mode to the SE internal SCSI drive.
 

Nixontheknight

Well-known member
Does anyone know of there is some of programmer switch procedure to disable a Mac SE Radius '020 accelerator on boot? My Floppy Emu doesn't work in HD mode with the accelerator, it would be nice to be able to disable the accelerator so I can copy from my Floppy Emu in HD mode to the SE internal SCSI drive.
if you have the radius control panel on your SCSI drive, you should be able to disable it from there, otherwise, you might have to remove the accelerator temporarily, copy the control panel on the SCSI drive, and reattach it
 

JC8080

Well-known member
if you have the radius control panel on your SCSI drive, you should be able to disable it from there, otherwise, you might have to remove the accelerator temporarily, copy the control panel on the SCSI drive, and reattach it
I downloaded the RadiusWare package from Macintosh Garden, it's supposed to install the proper drivers automatically. It installed Radius Accelerator and Radius Math extensions into the System 6 system folder, but it didn't add a control panel. I was expecting it would since other accelerators I have owned do have a control panel.

Do you know of a Radius control panel that applies to this board?
 

Phipli

Well-known member
This was posted yesterday replying to you and has exactly what you're asking for :
 

Nixontheknight

Well-known member
Does anyone know of there is some of programmer switch procedure to disable a Mac SE Radius '020 accelerator on boot? My Floppy Emu doesn't work in HD mode with the accelerator, it would be nice to be able to disable the accelerator so I can copy from my Floppy Emu in HD mode to the SE internal SCSI drive.
try holding down the mouse button when you turn your SE on, that'll allow you to switch the accelerator off
 

mg.man

Well-known member
Just cross-posting in case ppl land here...
SO that's Floppy EMU HD20 issues confirmed with Total Systems, MicroMac and now Radius accelerators. Does anyone know if Steve from BMoW still frequents our place?
 

Phipli

Well-known member
@bigmessowires ?

Probably timing issues - accelerators play merry havoc with timing. But, given many of the accelerators are close cousins and there are only fundamentally a small number of designs, reused by loads of firms (Applied Engineering, Total Systems, Extreme, Novy and Mobius, I think, all have extremely similar products. more besides), there is a chance that the accelerators never worked with the HD20 protocol. The cards/drivers will be patching the floppy driver to fix timings, perhaps they decided it wasn't worth doing the same for the HD20 specific code?
 

Phipli

Well-known member
Further to my last comment, many of these accelerators also added SCSI to pre-SCSI macs, so perhaps their answer was "buy a SCSI disk"?
 

cheesestraws

Well-known member
Pretty sure real HD20s don't work with accelerators either, at least on SEs. Since SCSI was so much better and SEs came with that, probably your answer here is to use SCSI, I'm afraid
 

Skate323k137

Well-known member
Pretty sure real HD20s don't work with accelerators either, at least on SEs. Since SCSI was so much better and SEs came with that, probably your answer here is to use SCSI, I'm afraid
I have a few FloppyEMU units. After I accelerated my SE, I talked with Steve (BMOW) and kinda left it at what you said. the accelerator breaks HD20 compatibility likely beyond his control and IMHO its not worth sinking time into so I didn't press the issue. He's always very responsive though.
 

Trash80toHP_Mini

NIGHT STALKER
Has anyone got a Plus with accelerator and FloppyEMU for testing? Curious about that config.

Agreed, accelerated machines with SCSI would be far edge cases for stock HD20 support, much less emulated mode.

Accelerators broke a lot of software that wasn't written within Apple spec. Bypassing ToolBox, directly addressing hardware was a huge no-no that was ignored much too often in the early days for minimal performance gains on badly hamstrung Macs. IIRC gaming for the most part?
 

mg.man

Well-known member
I have a few FloppyEMU units. After I accelerated my SE, I talked with Steve (BMOW) and kinda left it at what you said. the accelerator breaks HD20 compatibility likely beyond his control and IMHO its not worth sinking time into so I didn't press the issue. He's always very responsive though.
FYI...
 

Skate323k137

Well-known member
FYI...
Thanks for documenting it; effectively the same experience I had with my accelerated SE, using a MicroMac though.
 
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