ZX81 (1980 - ?)
The ZX80 was a precursor to the ZX81 and is contained under the same heading in the list. It was launched in January 1980 and cost £99.95 (or £79 if you bought it in kit form). It had a Z80A processor and a 4KB BASIC interpreter in ROM. In September 1980 a 16KB RAM pack was introduced. More information about the ZX80.
The ZX81 was launched in March 1981 and is an improvement on the ZX80 design. It contained a new special chip that replaced 18 chips in the ZX80 and sold for £69.95 (or £49.95 in kit form). There was also an add-on ROM sold that would upgrade a ZX80 to a ZX81. More information about the ZX81. Apparently the ZX81 is still (1998) produced for embedded systems, but without graphics.
There were also American clones produced. A Timex-Sinclair 1000 was the same as a ZX81. A Timex-Sinclair 1500 was the same as a ZX81 with a built-in 16KB RAM pack. More information about the clones.
There are 17 games listed for ZX81 in this list.
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