The LC III+ is simply an LC III bumped from 25 MHz to 33 MHz. The Performa 460 series (460, 466, 467) had identical hardware to the LC III+, but included additional application software. System Enabler 003 is for the LC III+. System Enabler 308 is for the Performa 460 series. Wait, what?
The mystery: Why two different System Enablers for the same hardware?
The LC III+ rolled out at the end of the LC III's life and didn't even get a proper badge (*hint* *hint*). It was just labeled "LC III". The Performa 460/466/467 launched for holiday sales in late 1993 and no more were produced. This possibly gives the Performa 460 the title of "shorted-lived Macintosh".
Let's start with just the revision of System Enabler 003 (for the LC III/LC III+). It was updated in April 1994, going from v1.0 to v1.1. Apple says "Updated in System Update 3.0. Minor bug fix for compatibility." But, when comparing v1.0 to v1.1 there is only one changed resource (besides the version number text).
In the gbly, Apple updated the timestamp to show this System Enabler is newer and added machine $0038. Convert that to decimal and add 6 to get the gestalt ID. That's 62, which is the LC III+ / Performa 460.
(To learn more about 'gbly' resources, see an older post
68kmla.org
That's the only change Apple made. No code changes. In other words, they simply told the operating system that System Enabler 003 works for both the LC III and the LC III+.
Why? Because Apple hadn't updated the badge on the LC III case. Users were told they needed System Enabler 003 for their "LC III", but were unable to boot because they actually had an LC III+. Add the LC III+ machine id to System Enabler 003 and the problem is solved.
So, does Enabler 003 (v1.1) work in the Performa 460 series as well? Yes! Same hardware. In fact, if you put both System Enabler 003 (v1.1) and System Enabler 308 (for the Performa 460) in the System Folder, then System Enabler 003 always gets chosen because it has the newest gbly timestamp. Ha! ha! ha!
Let's compare Enabler 003 and Enabler 308. Hmm. A lot more changes?
The only difference in the 'gbly' is the timestamp. Same machines are supported. 'MACS' and 'vers' are just different version numbers. 'lodr' is deleted. Presumably this was actually the same as the one built into the system and didn't need to be included in either version (v1.0 and v1.1) of System Enabler 003. Someone thoughtfully saved a little space by deleting the unchanged redundant 'lodr' from System Enabler 308.
'STR#' -16395 is the list of Macintosh computer names. It includes the text "LC III" because that isn't built into System 7.1's list. Unfortunately, whoever updated System Enabler 003 to v1.1 didn't bother adding the string "LC III+". And System Enabler 308 doesn't have "STR#' -16395. So, it doesn't give the System any new names at all, not even "LC III".
Here's what the About box should look like:
Here's what it looks like on the Performa 467. How sad. This Macintosh doesn't know it's name or what it looks like. This is the state that Apple in 1993 thought was acceptable.
Let's fix the System Enabler.
Fixing the name is easy. We just need to type the desired name into the gestalt ID location in 'STR#' -16395. Put "Macintosh LC III+" at the index of the gestalt id (62) in System Enabler 003. Now copy this resource over to System Enabler 308 and change the string to "Performa 460 Series". (Note: if you put both enablers in the system, System Enabler 003 wins due to the timestamp. So, "Macintosh LC III+" would win.)
Now for the exciting part. 'lpch' 48 is different between the two enablers. It turns out to be a red herring, but it got me looking. 'lpch' 48 updates gestalt information. Notice the text 'micn' early in the resource below? That's the gestalt selector for the machine icon!
Some other interesting numbers are:
"0003" is the default icon when a machine is unknown.
"BF89" is -16503, which is the Macintosh LC icon.
"BD98" is -17000, which is the Macintosh icon for a known computer without an icon.
Here are the icons in the vanilla System 7.1 System file. ICN# -17000 is missing, which is why no icon shows on the Finder about box for newer computers. (Aside: System 8.1 includes a default -17000 icon.)
Now let's look at the code portion of the 'lpch'. It gets the 'mach' machine id. Then, it checks to make sure it is less than $47 (71) which is the length of the table. If it is too big, it just sets it to zero to get the first icon number (which happens to be 0003 to represent "unknown"). Otherwise, it doubles the id (because each icon number is two bytes long) and looks it up on the table.
Therefore, if we count to the correct location in the table and change the icon for the LC III+ Performa 460 from "BD98" (-17000) to "BF89" (-16503) and reboot, we should get a proper icon. Ta da!
Hopefully this helps you understand a little bit more about System Enablers and Mac display identification. It may come in handy for those people that are in the process of hacking Macintosh computers into new form factors, and want to give it a proper new name.
Attached are the revised System Enablers, and the v1.0 of System Enabler 003 which I didn't see floating around elsewhere.
- David
The mystery: Why two different System Enablers for the same hardware?
The LC III+ rolled out at the end of the LC III's life and didn't even get a proper badge (*hint* *hint*). It was just labeled "LC III". The Performa 460/466/467 launched for holiday sales in late 1993 and no more were produced. This possibly gives the Performa 460 the title of "shorted-lived Macintosh".
Let's start with just the revision of System Enabler 003 (for the LC III/LC III+). It was updated in April 1994, going from v1.0 to v1.1. Apple says "Updated in System Update 3.0. Minor bug fix for compatibility." But, when comparing v1.0 to v1.1 there is only one changed resource (besides the version number text).
In the gbly, Apple updated the timestamp to show this System Enabler is newer and added machine $0038. Convert that to decimal and add 6 to get the gestalt ID. That's 62, which is the LC III+ / Performa 460.
(To learn more about 'gbly' resources, see an older post
Patched 6.0.8L for more Macs
D'oh... yes that's right, enablers are strictly a System 7 thing. I think my mind is so obsessed with a 475 running System 6 (just imagine how fast that would be) that I am ignoring fairly obvious obstacles to this happening. I guess that's the definition of a vanity project right there. :D
68kmla.org
That's the only change Apple made. No code changes. In other words, they simply told the operating system that System Enabler 003 works for both the LC III and the LC III+.
Why? Because Apple hadn't updated the badge on the LC III case. Users were told they needed System Enabler 003 for their "LC III", but were unable to boot because they actually had an LC III+. Add the LC III+ machine id to System Enabler 003 and the problem is solved.
So, does Enabler 003 (v1.1) work in the Performa 460 series as well? Yes! Same hardware. In fact, if you put both System Enabler 003 (v1.1) and System Enabler 308 (for the Performa 460) in the System Folder, then System Enabler 003 always gets chosen because it has the newest gbly timestamp. Ha! ha! ha!
Let's compare Enabler 003 and Enabler 308. Hmm. A lot more changes?
The only difference in the 'gbly' is the timestamp. Same machines are supported. 'MACS' and 'vers' are just different version numbers. 'lodr' is deleted. Presumably this was actually the same as the one built into the system and didn't need to be included in either version (v1.0 and v1.1) of System Enabler 003. Someone thoughtfully saved a little space by deleting the unchanged redundant 'lodr' from System Enabler 308.
'STR#' -16395 is the list of Macintosh computer names. It includes the text "LC III" because that isn't built into System 7.1's list. Unfortunately, whoever updated System Enabler 003 to v1.1 didn't bother adding the string "LC III+". And System Enabler 308 doesn't have "STR#' -16395. So, it doesn't give the System any new names at all, not even "LC III".
Here's what the About box should look like:
Here's what it looks like on the Performa 467. How sad. This Macintosh doesn't know it's name or what it looks like. This is the state that Apple in 1993 thought was acceptable.
Let's fix the System Enabler.
Fixing the name is easy. We just need to type the desired name into the gestalt ID location in 'STR#' -16395. Put "Macintosh LC III+" at the index of the gestalt id (62) in System Enabler 003. Now copy this resource over to System Enabler 308 and change the string to "Performa 460 Series". (Note: if you put both enablers in the system, System Enabler 003 wins due to the timestamp. So, "Macintosh LC III+" would win.)
Now for the exciting part. 'lpch' 48 is different between the two enablers. It turns out to be a red herring, but it got me looking. 'lpch' 48 updates gestalt information. Notice the text 'micn' early in the resource below? That's the gestalt selector for the machine icon!
Some other interesting numbers are:
"0003" is the default icon when a machine is unknown.
"BF89" is -16503, which is the Macintosh LC icon.
"BD98" is -17000, which is the Macintosh icon for a known computer without an icon.
Here are the icons in the vanilla System 7.1 System file. ICN# -17000 is missing, which is why no icon shows on the Finder about box for newer computers. (Aside: System 8.1 includes a default -17000 icon.)
Now let's look at the code portion of the 'lpch'. It gets the 'mach' machine id. Then, it checks to make sure it is less than $47 (71) which is the length of the table. If it is too big, it just sets it to zero to get the first icon number (which happens to be 0003 to represent "unknown"). Otherwise, it doubles the id (because each icon number is two bytes long) and looks it up on the table.
Therefore, if we count to the correct location in the table and change the icon for the LC III+ Performa 460 from "BD98" (-17000) to "BF89" (-16503) and reboot, we should get a proper icon. Ta da!
Hopefully this helps you understand a little bit more about System Enablers and Mac display identification. It may come in handy for those people that are in the process of hacking Macintosh computers into new form factors, and want to give it a proper new name.
Attached are the revised System Enablers, and the v1.0 of System Enabler 003 which I didn't see floating around elsewhere.
- David
The info you documented here is super cool! Great write up!
