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Tuesday, December 10, 2013

Laser 128 VTech reverse-engineered the Apple Monitor ROM

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Laser 128
The Laser 128 was a clone of the Apple II series of personal computers, first released by VTech in 1984.

Description

Unlike the Apple II clones from Franklin, VTech reverse-engineered the Apple Monitor ROM using a clean room design rather than copying it, as Franklin had. Apple Computer challenged VTech in court, but unlike its efforts directed at Franklin, Apple was unable to force the Laser 128 off the market. The Applesoft BASIC ROM was licensed from Microsoft and was completely legal.
As its name suggests, the $479 Laser 128 had 128 KB of RAM. Like the Apple IIc, it was a one-piece semi-portable design with a carrying handle and a single built-in 5¼-inch floppy disk drive. Unlike the Apple IIc, it had a numeric keypad, a Centronics printer port, and two Laser 128-only graphics modes. The computer also had a single Apple IIe-compatible expansion slot, which gave it better expansion capabilities than a IIc, but cards remained exposed; the slot was intended for an expansion chassis that provided slots compatible with the Apple's Slot 5 and Slot 7.[1]

Compatibility

InfoWorld found that the Laser 128 was incompatible with 12% of 129 tested software packages, mostly educational software or games. Compatible software included AppleWorks, Quicken, Apple Writer, VisiCalc, Flight Simulator II, The Print Shop, and Where in the World is Carmen Sandiego?.[1] It was aggressively marketed, both by mail order firms and in retail and catalog stores such as Sears. Even though its ROM was not derived from Apple's ROM, the Laser 128 series had a high degree of compatibility with its competition from Apple, and its popularity ensured that most major software companies tested their software on the Laser as well as on Apple hardware.
VTech owed much of this compatibility to the fact that they were able to license Applesoft BASIC (which constitutes the largest and most complex part of an Apple II's ROM contents) from Microsoft just as Apple did, heavily reducing the amount of code that had to be reimplemented. Microsoft had made most of its money by keeping the rights to the software that it sold to others. Likewise, Apple had failed to secure an exclusive distribution license for the Applesoft dialect of BASIC, and VTech was free to buy it. Much Apple software depended on various machine code routines that are a part of BASIC in ROM, and it's quite likely that the Laser would not have been as successful had it not had compatible ROM entry points. Apple countered the Laser 128 with its upgraded Apple IIc Plus. VTech responded with the Laser 128EX and the Laser EX2.
In 1988 VTech announced plans to release an Apple IIGS compatible that year for under $600.[2]

References

  1. ^ Jump up to: a b Field, Cynthia E. (1986-05-05). "Laser 128 Adds Bonuses to IIc". InfoWorld. p. 51. Retrieved 1 November 2013.
  2. Jump up ^ Ferrell, Keith (1988-04). "Computers Win Big!". Compute!. p. 6. Retrieved 10 November 2013.

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