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Introduced January 1977
Discontinued June 1979
Release Price     $1295

 

        This is Apple's first mass produced computer the Apple II. It was released in January of 1977 and took the home computer market by storm. The Apple II offered the home computer enthusiast what no other computer company to date had been able to supply, an easy to use home computer with color graphics built right into the computer at an affordable price. Steve Wozniak

        In early 1977 there were no real personal computers for the average home user. The market was full of hobbyist kits that took some level of technical understanding to put them together and there were the big box systems that were aimed at the business market and cost several thousands of dollars and even these required an "expert" to set them up. Then along came Apple with the Apple II, take it out of the box, connect it to the TV, plug in a tape cassette and viola you have a computer system in your home.   

      The earliest Apple IIs were sold with a number of RAM configurations ranging from 4K to 48K. This was made possible by a set of 3 switching blocks on the motherboard, one for each bank of  8 RAM chips in the RAM area. (see the picture above) The type of RAM chip you used was determined by the switching block that was plugged into the socket, either a 4K or 16K block. If you used 4K blocks your configuration was from 4 Kilobytes to 12 Kilobytes max. If you chose the 16K blocks your Ram size was 16 Kilobytes up to 48 Kilobytes. Since RAM was very expensive this system was necessary to keep the basic cost of the Apple II down.

       As prices for RAM dropped later releases of the Apple II were factory configured as 16, 32, or 48 Kilobyte systems. Apple discarded the 4K blocks and soldered the 16K blocks to the motherboard. The RAM chips were installed in the sockets 8 chips for each bank depending on how you ordered your system. The switching block system was completely done away with on the Apple II+ as the systems were only sold in the 48K configuration. This is one of the distinguishing features in determining if you have an Apple II or an Apple II+. Remember also that only the earliest Apple IIs had removable switching blocks, later IIs had them soldered in place at the factory. 

     There are several other features that distinguish the original Apple II from the Apple II+. The most obvious is the name plate on the cover. First there were a few different keyboards used in the Apple II and II+. The earliest Apple II keyboards did not have an encoder board attached to the underside of the keyboard and the lighted power key was raised up on an original Apple II (see the picture above). The Apple II+ lighted power key was flush with the case. I've seen a lot of auctions on ebay selling Apple IIs with the II+ keyboard installed claiming them to be original Apple IIs.

      An original Apple II does not auto-boot to BASIC, it boots to the built in Machine Language Monitor, known as the Sweet 16 Monitor written by Steve Wozniak, and fills the screen with random characters. You have to hold the "CTRL" and " B" keys  while turning on the computer to boot to the BASIC interpreter. This BASIC is not the same BASIC that is in all the Apple II computers from the II+ on. The original Apple II BASIC was hand assembled by Steve Wozniak.

      Another characteristic exclusive to the Apple II is the eight expansion slots are green with bolt down tabs (see picture above). The II+ expansion slots are black with no tabs.

      This Apple II was purchased at a local thrift store and added to the museum on February 21, 2003 and came with the original red cover user's manual.

 

System Architecture

   

Memory

 
Microprocessor MOSTEK 6502   Standard on system board 4k or 16k
Clock speed 1.023 MHz   Maximum on system board 48k
Bus type Apple Proprietary   Maximum total memory 64k using plug in board
Data bus width 8-bit   Memory speed and type 200ns dynamic RAM
Address bus width 16-bit   System board memory socket type 16 pin DIP
Interrupt levels N/A   Number of memory module sockets 24 socketed
DMA channels N/A   Memory used on system board TMS4116-20

Standard Features

   

Disk Storage

 
ROM size 16k   Internal disk and tape drive bays none
Optional math coprocessor no   Standard floppy drives tape or 5.25 Floppy
Parallel port type none   Optional floppy drives: up to 2 external
RS232C serial ports none   * 5 1/4 inch 143k yes
Mouse ports internal I/O socket   * 5 1/4 inch 1.2MB no
UART chip used N/A   * 3 1/2 inch 720k no
Maximum speed N/A   * 3 1/2 inch 1.44MB no
CMOS real time clock no   * 3 1/2 inch 2.88MB no
CMOS RAM no   Hard disk controller included no

Video & Graphics

   

Sound

 
Graphics Processor uses CPU   Sound Interface device uses CPU
Screen size - Col x Rows 40 x 24   Sound generation tone output to speaker
Resolution - Colors/High 6 / 280 x 192   ADSR capable no
Resolution - Colors/Low 16 / 40 x 48      
Max colors 16   Programming language  
Sprites or Missiles none   Built in language Apple BASIC
      Built in M L monitor yes

Expansion Slots

   

Keyboard Specs.

 
Total adapter slots 8   Number of keys 52
Number of 8/16/32 bit slots 8 / 0 / 0   Upper/lower case yes / no
      Keyboard cable length N/A

Physical Specs.

   

Environmental Specs.

 
* Height 4 1/4 inches   Operating voltage @ 60 Hz 120 VAC
* Width 15 1/4 inches   Maximum power supplied 60 WATTS
* Depth 17 3/4 inches   Power supply output - volts +5V/-5.2V/+11.8V/-12V
* Weight 11.5 pounds   Power supply output - amps