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32-bit Enabler Problems

Those of us on 32-bit dirty ROM machines like the Mac II, SE/30, IIx, and IIcx were pleased when Apple finally released the 32-bit Enabler for System 7.1. Unfortunately, this enabler appears to suffer from numerous bugs and quirks, but only for some people. I isolated a weird problem in which the 32-bit Enabler prevents MacsBug 6.2.2 from rebooting my SE/30 – the programmer’s switch works fine, as does MacsBug when I revert back to MODE32. Other people have related tales of woe that range from the Mac failing to boot to major speed hits and frequent crashes.

We haven’t identified any common factor other than the 32-bit Enabler. Some blame accelerators, but we know of one DayStar-accelerated Mac II that doesn’t work, and another DayStar-accelerated SE/30 that does. Rumors have floated about an incompatibility with third-party drive formatters, most notably Drive7 from Casa Blanca Works. John Catalano of Casa Blanca Works said they had only one call about this problem, and the call only relayed the Internet rumor. John said the Drive7 programmers are checking for problems, and users of Drive7 and the 32-bit Enabler who notice anything should contact Casa Blanca Works.

Ed Rotberg of Apple clarified one quirk. Apparently the 32-bit Enabler requires version 1.2 of the Mac II ROMs, which are only available as part of the $400 FDHD upgrade. Of course, Mac IIs also require a separate PMMU, but the ROM version problem confused many people who had been successfully using MODE32, which does not require the newer ROMs. Ed cautioned users to install the 32-bit Enabler loose in the System folder, since it won’t work in the Control Panel folder, for instance.

Roy McDonald of Connectix confirmed that Connectix has received complaints about the 32-bit Enabler (Connectix programmed MODE32, but had nothing to do with the 32-bit Enabler). Connectix recommends users follow this procedure:

  • First try the 32-bit Enabler. It works for many people just fine.
  • If your Mac won’t boot or won’t use 32-bit addressing, try MODE32. Connectix was unable to reproduce any conflicts between System 7.1 and MODE32 (they initially thought virtual memory might cause crashes with System 7.1 and MODE32), so MODE32 should work, and if you do experience problems with MODE32, let Connectix know.
  • If your Mac boots and goes into 32-bit addressing using the 32-bit Enabler, but you experience notable flakiness, add the Connectix Enabler Patch, which should be available from your favorite FTP site or commercial service. See TidBITS-162 for information on the patch, which is for use with all Enablers, including the 32-bit Enabler.

Why use the 32-bit Enabler? It can’t be turned off by extension managers. MODE32 can be turned off, and when you do this, MODE32 disables itself, turning off 32-bit addressing as well. When you turn MODE32 back on in the extension manager, MODE32 is still disabled, as is 32-bit addressing, and you have to re-enable MODE32 and 32-bit addressing manually before you can see all your memory again.

The items I launch at startup consume more memory than 24-bit addressing makes available, so if I forget to re-enable both MODE32 and 32-bit addressing, the Mac gets confused when it uses absolutely all of the available memory with ten more applications left to launch. If you boot with the Shift key down to avoid extensions, you get 24-bit addressing with either the 32-bit Enabler or MODE32, and MODE32’s settings and the Memory Control Panel’s settings aren’t changed for the next boot, which is nice.

We have version 1.0.3 of the 32-bit Enabler, which is the latest as far as we know, although we hope a 1.0.4 comes out relatively quickly to solve some of these problems.

Casa Blanca Works — 415/461-2227 — 415/461-2249 (fax)
Connectix — 800/950-5880 — 415/571-5100

Information from:
Ed Rotberg — [email protected]
Paul Duckenfield — [email protected]
John Catalano, Casa Blanca Works — [email protected]
Roy McDonald, Connectix — [email protected]

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