The Cambridge Computer Z88 was an A4-size, lightweight, portable Z80-based computer with a built-in combined word processing/spreadsheet/database application called PipeDream, along with several other applications and utilities, such as a Z80-version of the BBC BASIC programming language.
The Z88 evolved from Sir Clive Sinclair's Pandora portable computer project which had been under development at Sinclair Research during the mid-1980s. After Sinclair Research's existing computer business and the Sinclair brand were sold to Amstrad in 1986, a new company, Cambridge Computer Ltd., was formed to continue development. The Z88 was launched at the Which Computer? Show on February 17, 1987.
Despite the lightness of the Z88—it weighs 0.9 kg—its construction is surprisingly robust, including its membrane/chiclet keyboard which is both comfortable and almost inaudible (an optional electronic "click" can be turned on if it proves too quiet for the user's taste).
Powered by four AA batteries (giving up to 20 hours of use), the computer has three memory slots; each of which can be used for RAM expansion, removable mass storage, and proprietary program use. Since the slots use RAM, EPROM and ROM for their data transfer, the transfer speeds are usually very high. Although RAM cards of up to 1 MiB capacity were available, they were expensive. Most users used one or two 128 KiB cards.
Though the super-twisted LCD display has only eight lines, it is clear and surprisingly effective. In PipeDream, a miniature view of a whole page appears to the right of the display, giving a good feel for the overall layout, and compensating for the inevitable "letterbox" effect.
The 64 KBytes addresables by the Z80 processor are divided in four banks of 16 Kbytes each one. The 4 Mbytes of maximum memory for the system are also divided in 256 segments of 16 Kbytes each one. The hardware can map any of the 16 Kbyte blocks in any of the four banks. The first 512 Kbytes are reserved for ROM; the next 512 Kbytes block are reserved for internal RAM. The next three Mbytes are assigned to each one of the three memory slots.
It is also possible for an experienced user to replace the built-in 32 KiB RAM chip with a bigger 128 or 512 KiB static RAM chip. However, the latter requires some extra board modifications, and 512 KiB is the biggest size that can be addressed by the Z88 for the internal RAM. A same modification is possible for the internal EPROM slot. A 512 KiB flash EPROM chip can replace the original ROM. This allows an easy upgrade of the operating system.