problem with boot

[Arlo]

Hello, I recently picked up a Macintosh SE FDHD and it is having trouble booting from both the floppy drive and hard drive. When it tries to boot from the included system 7.0.1 boot disk it will give me a happy mac face and then think for a moment before spitting out the disk! Any info would be great!

 

[Dinotech]

trouble booting from both the floppy drive

You try start with "Install" or with "Disk Tools" disk?

With "Disk Tools":
If computer on boot detect hard disk with Mac OS, it don't starting boot from floppy drive. It start boot from hard disk and when booted, give you option access to floppy disk.
I think in Your situation:
1) computer detect Mac Os on hard drive
2) start booting from hadrd disk
3) hard disk is broken (or Mac Os with problems) - boot failed and computer show disk icon.

Disconnect hard disk from SE and try boot from floppy disk. If it boot Ok - problem with HDD or Mac OS. If still fail to boot, look what is with floppy disk

 

[Arlo]

Well sadly the top two screws have been ground down and I only have the 2 floppy’s that came with the machine

 

[Timo W.]

If computer on boot detect hard disk with Mac OS, it don't starting boot from floppy drive. It start boot from hard disk and when booted, give you option access to floppy disk.

That is complete nonsense. You can always boot from floppy. It has priority over the hard disk.

If the floppy disk is ejected, it is either not seen as being bootable, missing files for the Mac model, or simply incompatible.

Just create a new boot disk with a system that is known to work with the SE.

 

[Arlo]

That is what I was going to do I was just wondering if anyone had any other ideas

 

[Dinotech]

That is complete nonsense. You can always boot from floppy. It has priority over the hard disk.

Nonsense or not, but faced that about 3 days back on Mac Classic (M0420.) When boot with "Disk Tools" floppy - it ignored floppy disk (not rejecting) and boot from hard disk Mac OS, where show "Disk Tools" as option to start. But if i clear all partitions from linux for that HDD - yes, i can boot Mac from "Disk Tools" floppy disk. "Installation" disk allways boot as priority. In my case no story about broken floppy or disk image. Strange, but fact. I try that with 7.0.1 and with 7.1 - the same results.

About @Arlo problem - if is some other floppy, try @Timo W. version, if no other floppy disk - disconnect hard disk and try boot from floppy for test.

Tell us about results, please.

 

[Arlo]

Will do

 

[GiGaBiTe]

The SE is a 24 bit addressing machine with the 68000 CPU, so the last OS with the best compatibility with the machine is 6.0.8. 7.x introduced 32 bit addressing for later 68020/030/040 Macs that is incompatible with the SE. It also uses a lot more RAM than 6.0.8, which is at a premium on the SE because of the 4 MB RAM limit.

I could never get 7.0.1 working on my SE FDHD reliably, I had to use 7.1.2, and it was a whole lot slower than 6.0.8.

 

[Svenska]

System 7.x does not require 32-bit addressing. Any version up to 7.5.3 - including 7.0.1 - runs just fine on straight 68000-based machines and opens up a much larger software library.

System 6 is a lot faster, though. Also note that 6.0.8 was never localized; most localized versions stopped at 6.0.7.

 

[GiGaBiTe]

System 7.x does not require 32-bit addressing. Any version up to 7.5.3 - including 7.0.1 - runs just fine on straight 68000-based machines and opens up a much larger software library.

And opens the system to some very serious software incompatibility that can take down the entire system.

Example, try to run Beyond Dark Castle on System 7. It will clobber the machine the moment the game is launched. Say goodbye to all of your hard drive partitions.

There are numerous 24 bit programs like this that are not 32 bit compatible, just leaving 32 bit addressing off will not fix the issue. There is very little software from the System 7 era that is practical to use on a SE. Not only do you have memory limits to worry about, but most later System 7 software expects a resolution of 640x480 at minimum and color or greyscale modes to be available, none of which exists on the SE.

The memory limit on the SE is actually a lot worse than it looks. While the system can have 4 MB of RAM installed, the largest contiguous block of memory is less than half of that, which limits large programs from being used. Apple in their infinite wisdom peppered memory mapped devices inside the address space where RAM resides, eating into the available memory and fragmenting it. Some CPU upgrade cards like the TotalSystems Gemini Ultra can use the MMU in the 68030 to reallocate memory mapped devices elsewhere in the address space, but not all of them. So it frees up a bit more memory programs can use, but not enough to run larger programs that need say more than 2-3 MB at a time.

I have a SE FDHD myself, and I speak from experience that it is not a good idea to run System 7+ on these machines.

 

[Svenska]

And opens the system to some very serious software incompatibility that can take down the entire system. Example, try to run Beyond Dark Castle on System 7.

That is part of the system design; the more I look into Mac OS, the more horrified I am. That doesn't change that a particularly badly written application trashing your system is still at fault - and not the system.

In DOS, programs are always free to trash your partition table. It's a risk you take very time you run anything. Same for Macs.

There are numerous 24 bit programs like this that are not 32 bit compatible, just leaving 32 bit addressing off will not fix the issue.

I don't understand. System 7 on a compact Mac cannot turn on 32-bit addressing because the hardware does not support it. Why does it matter if System 7 supports it on later machines?

Turning off 32-bit addressing reduces the usable memory to 8 MB and gets you the old 24-bit addressing. It obviously doesn't fix issues caused other incompatibilities with earlier System versions, but it will fix everything related to 24-bit addressing.

There is very little software from the System 7 era that is practical to use on a SE.

Maybe. But there seems to be quite a bit of early System 7 software which is usable on a compact Mac and won't run on System 6.

 

[GiGaBiTe]

That is part of the system design; the more I look into Mac OS, the more horrified I am. That doesn't change that a particularly badly written application trashing your system is still at fault - and not the system.

In DOS, programs are always free to trash your partition table. It's a risk you take very time you run anything. Same for Macs.

I've never seen a DOS program trash a partition table, besides viruses like Windows 9x. Not to say it isn't possible, but it's a vanishingly rare occurrence compared to rolling the dice with 24 bit programs on System 7.

I don't understand. System 7 on a compact Mac cannot turn on 32-bit addressing because the hardware does not support it. Why does it matter if System 7 supports it on later machines?

SE/30, Classic II, CC and CC II can all use 32 bit addressing owing to a 68030 CPU. 68020/030/040 upgrade boards can also sometimes take advantage of it.

It matters that System 7 supports 32 bit addressing because System 7 makes some assumptions about the underlying hardware that make it not 100% compatible with 24 bit software, even with 32 bit addressing off.

It's why Beyond Dark Castle crashes, System 7 is reading the upper 8 bits used as status flags and going off into la la land until it implodes and bye bye partition table.

Maybe. But there seems to be quite a bit of early System 7 software which is usable on a compact Mac and won't run on System 6.

Do you have any examples? Early System 7 applications that actually required System 7 usually were requiring System 7 features, or hardware that was designed to run it. The 512x342 1 bit screen and overburdened 68000 made it not a good time to run such software.