The revised Macintosh Portable adds a software-controlled backlit monochrome screen and pseudostatic memory to Apple's original battery-powered Macintosh design.
Backlit active-matrix monochrome LCD, 640 × 400 pixels and 1-bit colour; 9.8-inch diagonal from EveryMac. Apple’s 1991 developer note confirms adjustable backlighting through its control panel, keyboard sequences and application software; no LCD subtype or native refresh published
Performance
Processor
MC68HC000 16 MHz (Macintosh Portable)
CPU cores
1
Memory
2 MB or 4 MB
Storage
40 MB
CPU
CMOS Motorola MC68HC000 at 16 MHz; no floating-point unit, MMU or CPU cache. The 1991 developer note specifies zero-wait-state expansion RAM access and slower timing in idle mode
Memory type
Pseudostatic RAM replaces the original machine’s SRAM; 2 MB or 4 MB retail configurations with 256 KB ROM. Apple’s developer note describes a keyed 50-pin RAM connector with changed pin assignments and expansion to 8 MB with timing qualifications; original cards are not universally interchangeable
Storage type
40 MB internal SCSI hard disk and one 1.44 MB FDHD SuperDrive floppy in the new retail configurations, according to contemporary TidBITS coverage and Apple’s March 1991 service guide. The 40 MB configuration is stored as 40/1024 GB for the site’s MB formatter
Connections
Operating system
macOS
Port detail
One ADB port, external floppy port, DB-25 SCSI, two RS-232/RS-422 serial ports, stereo sound output, power connector and video output. Apple’s guide also lists optional ROM, RAM and 2400 bit/s modem expansion and a 96-pin processor-direct slot; no Ethernet or USB
Keyboard
Built-in Macintosh-layout keyboard and 1.3-inch trackball; 18-key numeric keypad can replace the trackball. The keyboard and trackball can be arranged for left-handed use
Trackpad
Built-in trackball; no trackpad
In the box
Exact first-sale day and month unconfirmed. Apple announced order availability on 11 February 1991, according to that day’s TidBITS; July recall coverage says certain adapters began shipping with the backlit model in March. Apple’s June 1991 support article confirms the control panel shipped with new computers, establishing retail delivery during 1991. The announcement is not used as a first-delivery date
Battery and size
Battery life detail
Lead-acid main battery. Contemporary TidBITS coverage gives 3–6 hours with backlighting, not a fixed maker runtime; no headline runtime inferred. Apple’s combined original/backlit support table lists 15.8 lb and closed dimensions of 4.05 × 15.25 × 14.83 inches (height × width × depth); exact revised-model metric figures were not established
Charger
Apple’s March 1991 service guide gives 85–270 V AC, 48–62 Hz and 15 W maximum, while its later combined support table gives 70–270 V and a 5 W figure; these are not treated as interchangeable claims
Configurations
Processor
Memory
Storage
MC68HC000 16 MHz (Macintosh Portable)
2 MB
40 MB
MC68HC000 16 MHz (Macintosh Portable)
4 MB
40 MB
Pros and cons
Pros
+Adjustable screen backlight
+Replaceable lead-acid battery
+Reversible keyboard and trackball layout
Cons
−Heavy portable enclosure
−RAM expansion cards differ from the original model
