Macintosh SE

SE stands for "System Expansion", not like in Windows, "Second Edition". Macs SE had many inprovements over Plus. First, it had internal SCSI bus and some models were sold with internal hard drive (20MB or 40MB) or with second floppy drive. SE had a special expansion bus inside allowing to use better CPU or bigger RAM. More, Apple added ADB - an universal keyboard/mouse bus which became standard for all early Macs.

Model No: M5010

Year: 1988
Discontinued: 1990
CPU: Motorola 68000 8MHz
Max. RAM: 4MB
RAM Type: 30-pin SIMMs
Hard disk: 20MB SCSI, 3.5" FH
Floppy drives: 1 1.4MB 3.5"
Other drives: None
Graphics: 512x342 monochrome
Sound: 1 8-bit/22kHz speaker
Display: Built-in 9" CRT
Dedicated OS: Mac System 3.3

Maximum OS: Mac System 7.5.5

Expansions: ADB, internal expansion connector.

Peripherals in collection:
 - ADB keyboard and mouse

Connectors:  - 2 ADB connectors for keyboard and mouse
 - External floppy connector
 - External SCSI connector
 - 2 RS-422 serial ports (for printer and modem)
 - Mono Jack sound output.

The story of this computer is long and strange. Outside, the only trace of its source is a solid metal plate which was glued to the front of computer, with German text saying that it's a gift from Humboldt Foundation. More can be read from inventory numbers, hard drive data scraps, filesystem and software used.
After buying by Humboldt Foundation, it was upgraded to 4MB of RAM and Miniscribe 20MB SCSI Winchester hard drive, which replaced one of two floppy drives. They also changed floppy drive to 1.4MB version. In Poland it was used in some University (?Physics? Maths? - as I suspect from the software on its hard drive, as documents were deleted), probably somewhere near Warsaw, as there were conversion tools for character encoding standards popular there. It was used much, especially for text editing in WriteNow and TeX, as the most frequently used application is a text and formula editor.
Somewhere around 1992 the owner had changed, Mac was probably given to retired worker or something like this. It was used at home as a typewriter and... a musical instrument, which played songs from notes using software. It was playing to 1993 or 1994, when was finally turned off for next 15 years. As I remember I found this unit in recycling plant, in a big dump of electronic garbage received by supermarkets for discounts in new computers.

Interesting facts...

On the left side of the computer you can see 2 buttons. If not, you have to look into grilles there - they will be 2 big push buttons. One of them resets computer while another one runs internal debugger. This small piece of software pops in as a white rectangle with text cursor and allows to do simple operations in memory, reading, dumping, writing bytes, executing programs or running program in memory from specified offset.

You can run a hidden program from SE's ROM: You have to press debugger button and type:
G 41D89A. It will show development team's photos!. SE ROM used only 89K, but Apple used 256K chip there. Because it was a ROM, all its contents was designed by Apple engineers. The price for making 256K ROM chip with 89K of software was the same as a full 256K. So to fill this chip, engineers put their photos in ROM with small routine which, if launched from its beginning, shows photos on screen. 

If you type "G 4188A4" there and press Enter, you'll get message "Stolen from Apple Computers". This small bitmap was a trap for companies who wanted to copy Macintosh including its ROM and sell it as their own product. Some companies did it, but they made a new, compatible ROM (for example Executor emulator contained re-written ROM to run Mac programs on PC - thanks to Jorpho for info). Some others just copied a whole ROM changing "Apple" to their name in all strings. Because "find-and-replace" works only with text, not bitmaps, this "Stolen from Apple" survives any changes except deep analysis of ROM... which was done only while writing a new one. This was an easy proof that ROM was copied.
Another "easter egg" comes with System 6 - if you click version number in Chooser. It reads "By Scott Douglas, fjs, & jhl"

There were many peripherals for it. SE was known from its laser printers support, but paper had to be loaded manually. Some third-party companies sold a special feeder to SE's laser printer (source: Bajtek, 1991):