HOME
The Info List - Mac Plus



--- Advertisement ---


(i) (i) (i)

The MACINTOSH PLUS computer is the third model in the Macintosh
Macintosh
line, introduced on January 16, 1986, two years after the original Macintosh and a little more than a year after the Macintosh 512K , with a price tag of US$2599. As an evolutionary improvement over the 512K, it shipped with 1 MB of RAM standard, expandable to 4 MB, and an external SCSI
SCSI
peripheral bus, among smaller improvements. It originally had the same generally beige-colored case as the original Macintosh
Macintosh
("Pantone 453" ), but in 1987, the case color was changed to the long-lived, warm gray "Platinum" color. It is the earliest Macintosh
Macintosh
model able to run System 7 OS.

CONTENTS

* 1 Overview * 2 Long production life

* 3 Problems

* 3.1 ROM revisions

* 4 Emulators * 5 Timeline of compact Macintosh
Macintosh
models * 6 See also * 7 References * 8 External links

OVERVIEW

Introduced as the Macintosh
Macintosh
Plus, it was the first Macintosh
Macintosh
model to include a SCSI
SCSI
port, which launched the popularity of external SCSI devices for Macs, including hard disks, tape drives, CD-ROM drives, printers, and even monitors. The SCSI
SCSI
implementation of the Plus was engineered shortly before the initial SCSI
SCSI
spec was finalized and, as such, is not 100% SCSI-compliant. SCSI
SCSI
ports remained standard equipment for all Macs until the introduction of the iMac in 1998, which replaced most of Apple's "legacy ports " with USB
USB
.

The Macintosh Plus
Macintosh Plus
was the last classic Mac to have a phone cord-like port on the front of the unit for the keyboard , as well as the DE-9 connector for the mouse ; models released after the Macintosh
Macintosh
Plus would use ADB ports.

The Mac Plus was the first Apple computer to utilize SIMM memory instead of single DIP DRAMs. Four slots were provided and the computer shipped with four 256k SIMMs for 1MB total. By replacing them with 1MB SIMMs, it was possible to have 4MB of RAM. Although 30-pin SIMMs could support up to 16MB total RAM, the motherboard had only 22 address lines connected for 4MB.

It has what was then a new 3.5-inch double-sided 800 KB floppy drive , offering double the capacity of floppy disks for previous Macs, along with backward compatibility. The then-new drive is controlled by the same IWM chip as in previous models, implementing variable speed GCR . The drive was still completely incompatible with PC drives. The 800 KB drive has two read/write heads, enabling it to simultaneously use both sides of the floppy disk and thereby double storage capacity. Like the 400 KB drive before it, a companion Macintosh
Macintosh
800K External Drive was an available option. However, with the increased storage capacity combined with 2-4x the available RAM, the external drive was less of a necessity than it had been with the 128K and 512K.

The Mac Plus has 128 KB of ROM on the motherboard, which is double the amount of ROM that's in previous Macs; the then-new System software and ROMs included routines to support SCSI, the then-new 800 KB floppy drive, and the Hierarchical File
File
System (HFS), which uses a true directory structure on disks (as opposed to the earlier MFS, Macintosh
Macintosh
File
File
System in which all files were stored in a single directory, with one level of pseudo-folders overlaid on them). For programmers, the fourth Inside Macintosh volume details how to use HFS and the rest of the Mac Plus's new system software. This new filing system allows it to use the first hard drive Apple developed for the 512K, the IWM floppy disk-based Hard Disk 20 and the then-new ROMs allow the Macintosh
Macintosh
to use the drive as a startup disk for the first time. The Plus still did not include provision for an internal hard drive and it would be over nine months before Apple would offer a SCSI drive replacement for the slow Hard Disk 20. It would be well over a year before Apple would offer the first internal hard disk drive in any Macintosh.

A compact Mac , the Plus has a 9-inch (23 cm) 512×342 pixel monochrome display with a resolution of 72 PPI , identical to that of previous Macintosh
Macintosh
models. Unlike earlier Macs, the Mac Plus's keyboard includes a numeric keypad and directional arrow keys and, as with previous Macs, it has a one-button mouse and no fan, making it extremely quiet in operation. The lack of a cooling fan in the Mac Plus led to frequent problems with overheating and hardware malfunctions.

The applications MacPaint and MacWrite were bundled with the Mac Plus. After August 1987, HyperCard and MultiFinder were also bundled. Third-party software applications available included MacDraw , Microsoft Word , Excel , and PowerPoint , as well as Aldus
Aldus
's PageMaker . Microsoft Excel and PowerPoint (originally by Forethought ) were actually developed and released first for the Macintosh, and similarly Microsoft Word 1 for Macintosh
Macintosh
was the first time a GUI version of that software was introduced on any personal computer platform. For a time, the exclusive availability of Excel and PageMaker on the Macintosh
Macintosh
were noticeable drivers of sales for the platform. The Apple Macintosh Plus at the Design Museum in Gothenburg
Gothenburg
, Sweden
Sweden

The case design is essentially identical to the original Macintosh
Macintosh
. It debuted in beige and was labeled Macintosh Plus
Macintosh Plus
on the front, but Macintosh Plus
Macintosh Plus
1 MB on the back, to denote the 1 MB RAM configuration with which it shipped. In January 1987 it transitioned to Apple's long-lived platinum-gray color with the rest of the Apple product line, and the keyboard's keycaps changed from brown to gray. In January 1988, with reduced RAM prices, Apple began shipping 2- and 4- MB configurations and rebranded it simply as " Macintosh
Macintosh
Plus." Among other design changes, it included the same trademarked inlaid Apple logo and recessed port icons as the Apple IIc and IIGS before it, but it essentially retained the original design.

An upgrade kit was offered for the earlier Macintosh 128K and Macintosh 512K /enhanced , which includes a new motherboard, floppy disk drive and rear case. The owner retained the front case, monitor, and analog board. Because of this, there is no " Macintosh
Macintosh
Plus" on the front of upgraded units, and the Apple logo is recessed and in the bottom left hand corner of the front case. However, the label on the back of the case reads " Macintosh Plus
Macintosh Plus
1MB". The new extended Plus keyboard could also be purchased. Unfortunately, this upgrade cost almost as much as a new machine.

The Mac Plus itself can be upgraded further with the use of third-party accelerators. When these are clipped or soldered onto the 68000 processor, a 32 MHz 68030 processor can be used, and up to 16 MB RAM. This allows it to run Mac OS 7.6.1 .

There is a program available called Mini vMac that can emulate a Mac Plus on a variety of platforms, including Unix
Unix
, Windows , DOS
DOS
, classic Mac OS , macOS , Pocket PC , iOS and even Nintendo DS .

LONG PRODUCTION LIFE

The "ED" at the end of the model name indicates that this Macintosh
Macintosh
was sold to the educational market.

Although the Mac Plus would become overshadowed by two new Macs (the Macintosh SE and the Macintosh II ) in March 1987, it remained in production as a cheaper alternative until the introduction of the Macintosh Classic
Macintosh Classic
on October 15, 1990. This makes the Macintosh
Macintosh
Plus the longest-produced Macintosh
Macintosh
ever. It continued to be supported by versions of the classic Mac OS up to version 7.5.5 , released in 1996. Additionally, during its period of general market relevance, it was heavily discounted like the 512K/512Ke before it and offered to the educational market badged as the " Macintosh Plus
Macintosh Plus
ED". Due to its popularity, long life and its introduction of many features that would become mainstays of the Macintosh
Macintosh
platform for years, the Plus was a common "base model" for many software and hardware products.

PROBLEMS

The lack of fan could cause the life of a Macintosh Plus
Macintosh Plus
to end early for some users. As the power supply would heat up, solder joints inside it would fracture causing many problems, such as loss of deflection in the monitor or a complete loss of power. As in most early compact Macs, the problem was common in the yoke connector, flyback transformer, and horizontal drive coupling capacitor. A fan was also often added to reduce heat when the machine was upgraded to its full RAM capacity of 4 MB.

From the debut of the Macintosh 128K through the Macintosh
Macintosh
Plus, various third-party cooling add-ons were available to help increase airflow through the unit. Apple reorganized the compact Macintosh
Macintosh
case to accommodate a fan with the release of the Macintosh SE , which included a heat-generating internal hard disk.

ROM REVISIONS

The Plus went through two ROM revisions during its general market relevance. The initial ROM was replaced after the first two months as it had a serious bug which prevented the Mac from booting if an external SCSI
SCSI
device was powered off. The second revision fixed a problem with some SCSI
SCSI
devices that could send the Mac into an endless reset at startup.

EMULATORS

* MESS
MESS
* Mini vMac

TIMELINE OF COMPACT MACINTOSH MODELS

See also: Timeline of Apple Macintosh models

SEE ALSO

* Macintosh 512K * Macintosh SE * Macintosh Classic
Macintosh Classic
* Macintosh 512Ke * Macintosh XL

REFERENCES

* ^ "The 25 Greatest PCs of All Time". PCWorld. 2006-08-11. Retrieved 2016-05-20. * ^ "History of computer design: Apple Macintosh". Landsnail.com. 1998-05-17. Retrieved 2016-05-20. * ^ "History of computer design: Macintosh
Macintosh
Plus". Landsnail.com. 1998-05-17. Retrieved 2016-05-20. * ^ Knight, Dan. "ScuzzyGraph and ScuzzyGraph II". Low End Mac. Retrieved 10 July 2015. * ^ "Mac Plus". Low End Mac. Retrieved 2016-05-20. * ^ * ^ "Classic Mac Repair Notes" (PDF). 68kmla.org. Retrieved 2016-05-20. * ^ Still Useful after All These Years -- The Mac Plus * ^ "Technical Notes". Developer.apple.com. Retrieved 2016-05-20. * ^ "Technical Notes". Developer.apple.com. Retrieved 2016-05-20.

.