Apple IIc Plus

The Apple IIc Plus is the final model in the Apple IIc line, introduced by Apple Computer, Inc. in September 1988. It featured a faster 4 MHz 65C02 CPU, an internal 3.5" floppy drive, and several architectural enhancements over its predecessor, the Apple IIc.

Apple IIc Plus

Apple IIc Plus
Specifications
Manufacturer	Apple Computer, Inc.
Type	Home computer
Released	September 1988
Discontinued	November 1990
Intro price	US$675 (1988)
CPU	MOS Technology 65C02 @ 4 MHz
Memory	128 KB RAM (expandable to 1 MB)
Storage	Internal 3.5" (800 KB) floppy disk drive, external 5.25" supported
Display	40×24 or 80×24 text, 280×192 (colour), 560×192 (monochrome) graphics
Sound	1-bit speaker (toggle), same as Apple II series
Dimensions	30.5 cm × 29.2 cm × 7.6 cm
Weight	3.6 kg
OS / Firmware	Apple DOS 3.3, ProDOS, Apple Pascal
Predecessor	Apple IIc
Successor	Apple IIGS
Codename	Raisin
Model no.	A2S4500

Architecture and Processor

The IIc Plus is powered by a 65C02 microprocessor running at 4 MHz, a significant speed increase over the original IIc’s 1 MHz. The system uses a custom ASIC for memory and peripheral management, and retains the IIc’s all-in-one compact design with built-in keyboard and power supply.

Key architectural features:

• CPU: MOS Technology 65C02 @ 4 MHz (software switchable to 1 MHz for compatibility)
• ASIC: Custom Apple chip integrates memory, I/O, and timing functions
• ROM: 32 KB (with built-in firmware for ProDOS, AppleSoft BASIC, and utility routines)
• System bus: 8-bit data, 16-bit address (64 KB addressable per bank)

Memory and Storage

The IIc Plus shipped with 128 KB RAM as standard, expandable up to 1 MB via third-party memory cards. The system features a built-in 3.5" double-sided 800 KB floppy disk drive, replacing the earlier IIc’s 5.25" drive. An external 5.25" drive can still be attached for backward compatibility.

• RAM: 128 KB (expandable to 1 MB)
• ROM: 32 KB
• Internal storage: 3.5" Sony floppy (800 KB, GCR encoding)
• External storage: Optional 5.25" floppy (140 KB), compatible with UniDisk 3.5 and external drives

Display and Graphics

The IIc Plus supports the same video modes as earlier Apple II models, with both colour and monochrome output:

• Text: 40×24 or 80×24 characters (with 80-column card)
• Graphics:
  • Low-res: 40×48 (16 colours)
  • High-res: 280×192 (6 colours)
  • Double hi-res: 560×192 (monochrome)
• Video output: Composite video (NTSC), RGB via third-party adapters

Sound Capabilities

Sound is generated via a simple 1-bit speaker, toggled directly by software, as in all Apple II models. No dedicated sound chip is present, but third-party sound cards are supported.

• Speaker: Internal, 1-bit digital (toggle)
• Expansion: Supports Apple II-compatible sound peripherals

Input/Output and Expansion

The IIc Plus maintains the IIc’s compact, closed-case design, but provides a range of built-in ports for peripherals and expansion:

• Serial ports: Two DIN-5 (modem and printer)
• Video: Composite video output (RCA), monochrome output (DIN-8)
• Disk port: For external 5.25" or 3.5" drives
• Joystick/mouse port: DE-9 connector
• Audio: Internal speaker only
• Keyboard: Integrated
• Expansion: Internal memory expansion slot (up to 1 MB), no standard Apple II slots

Gallery

• 
  Apple IIc Plus front view
• 
  Side view with Floppy Drive
• 
  Rear panel with I/O ports
• 
  Internal logic board