Turbo040 in SE/30 "bad F-line instruction"

[JRL]

Hey all,

I recently purchased a Turbo040 + Twinspark adapter (bundled) and I am having weird issues. The Turbo040 seems to work great but I get a "bad F-line instruction" error on about 90% of all of the things I've tried to run. 

The SE/30 was recapped by me and had no prior problems before recapping. I have not done the analog board though yet - I do not have these issues without the 040.

The Turbo040 works great in a IIci (also recapped). But it also has these F-line errors at a smaller degree.

Specs:

Stock ROM

7.1

32 MB RAM

SCSI2SD v5.1

Thanks!

-J

 

[pcamen]

Anyone? Anyone? Bolle? Anyone?

 

[Bolle]

What hardware revision of the Turbo are we talking about? Which firmware version is installed and what version of the init/cp are you using?

I have seen that the Turbo is sometimes having issues with the original Twinspark but it’s weird that you are getting errors in the IIci as well.

It could be that it’s some 040 software incompatibility of something you’ve got installed on both machines.

 

[JRL]

@Bolle Unfortunately I can't even figure out what firmware is installed as the CP crashes with an F-line error when i try to click get info.

https://imgur.com/a/R48KWhB

I am running 2.3 of the CP (from LEM)

Re: software causing the errors, I was thinking this too, but on the IIci I get the same F-line errors on software that should definitely be 040 compatible (Aldus Pagemaker 5.0, ClarisWorks 2.0, among others)

 

[Bolle]

Does this happen as well without the Turbo control panel installed?

As for software incompatibility I was more thinking of something OS related. Did you do a clean install with „software for any Macintosh“ selected?

That‘s what you’re actually supposed to do according to the manual I think.

Edit: something else just struck my mind. Aren’t F-line errors often related to FPU woes? Did you check if you maybe have a LC040 installed on your Turbo?

 

[JRL]

Does this happen as well without the Turbo control panel installed?

As for software incompatibility I was more thinking of something OS related. Did you do a clean install with „software for any Macintosh“ selected?

That‘s what you’re actually supposed to do according to the manual I think.

Yeah, exact same symptoms without the Turbo panel.

I haven't tried a new system install but I'll give it a shot! It is a relatively fresh install, but yes I only installed "software recommended for this Macintosh" so I do think you have a point. Thanks Bolle!

EDIT: I haven't checked, but I'm pretty sure it's a full 040. I'll do so soon though. Dumb question but is the T040 heatsink easy to take off?

 

[JRL]

Welp, Techtool reports it as having no FPU. I guess I can't really complain for the price I bought it for - unfortunately I have no other 040s at all. I just picked up a full 40 MHz 040, will report back.

It does look like there was a model without FPU, so I still find it strange that there's still a lot of incompatibility.

 

[Bolle]

Hmmm. Not sure but it's possible the Turbo040i (LC040 chip from the factory) had different firmware. I might mix that up with the Value040 though. I have seen firmware images with the same version number but different checksums.

Popping in a full 040 might be a thing to try though just to be sure.

 

[JRL]

I did think of something. The Turbo040 came from Artmix originally, maybe it was a Turbo040i mistakenly flashed with firmware meant for the 040? 

The chip does have a date of 1998.

 

[JRL]

Also, I did do a clean universal install and nothing has changed unfortunately.

 

[Crutch]

To be clear these error are 100% reproducible?  If so it seems likely that it is indeed crashing out looking for an FPU.  What happens if you install something like SoftwareFPU to trick the machine into thinking it has an FPU?  That might prevent the crashes as a short term fix.  (I have no idea if SoftwareFPU even runs with an 040, but I think it would.)

 

[BadGoldEagle]

From the SoftwareFPU Macintosh Garden download page:

Because of a 68LC040 CPU chip bug, some applications crash with SoftwareFPU on 68LC040 Macintosh.

Still worth a try! I concur with Crutch. I think the lack of FPU is causing this crash.  

 

[johnklos]

Someone should make a binary patcher. Floating point exceptions will work on older LC040s so long as the previous instruction to any FPU instruction is not a write. It'd be tricky because you can't change the size of the executable section reliably unless you can also patch all jumps and call addresses, but a patcher could just make an external location where the write + FPU calls are overwritten with a call to the same write, a NOP, then the FPU operation, then a return.

Amigas had a program called CyberPatcher which would patch Amiga binaries at load time to replace instructions which are emulated on the m68060 with calls, since they're faster than a full exception.

 

[JRL]

Thanks for the suggestions! Yeah, the F-line errors happen every single time on the applications that cause it. 

As an update, I did try both versions of SoftwareFPU - I either get an F-line or address error, depending on the specific combinations of cache settings. When SoftwareFPU is loaded I do not always get the same error, sometimes it just hangs.

Ugh  At least I got a partial refund (covering the cost of the new 040 + a bit extra).

 

[JRL]

Just as a followup, a proper 040 with FPU did fix this issue. Yay!