Nova

a [|16-bit] [|minicomputer] series built by the American company [|Data General] starting in 1968. The Nova was designed by DEC PDP-8 chief engineer and Data General co-founder [|Edson de Castro]. It was packaged into a single [|rack mount] case.
 * Home * Hardware * Nova**
 * [[image:Data_General_NOVA_System.jpg width="160" link="https://commons.wikimedia.org/wiki/File:Data_General_NOVA_System.jpg"]] ||~ || **Nova**, (Data General Nova)

Unlike the PDP-8, Nova was a [|load/store architecture]. It had four 16-bit [|accumulators], where two could be used as [|index registers], and a 15-bit [|address space] and [|PC]. The Nova is a big-endian architecture. Since there is no byte addressing, bytes need to be parsed out of words using swaps and masks high-order byte first. Nova consists of a nibble-serial 4-bit ALU - its [|RISC-like] instructions perform arithmetical and logical operations with the options to rotate, test and branch on the (skip next instructon on zero, carry) the 17-bit result, and also to discard the result otherwise written into the target accu. Basic models of the Nova came without built-in hardware multiply and divide. The first models were available with 1 to 8 Kibi words of magnetic core memory.

[|System software] provided include the [|real time operating system] [|RDOS], assembler, Basic interpreter, and Fortran and Algol compiler, expanded with Forth, Lisp, and C through third party vendors. toc =Nova Line=
 * NOVA Rack ||~ ||^ ||
 * NOVA Rack ||~ ||^ ||

SuperNOVA
The SuperNOVA subsequently replaced initial magnetic core memory with faster ROM for library routines, and semiconductor (SuperNOVA SC) memory. The 4-bit ALU was extended to 16-bit using four instead of one [|bit slice] [|74181] ALU with speedup correspondingly. 

Nova 1200
The Nova 1200 contained the entire CPU one one board, first shipped in 1971. It still had the Nibble-serial ALU, and up to 32 Kibi words magnetic core memory. 
 * [[image:320px-Nova1200.agr.jpg link="https://commons.wikimedia.org/wiki/File:Nova1200.agr.jpg"]] ||
 * Nova 1200 Front panel ||

Nova 8x0
The faster Nova 800 was released in 1971. The Nova 840 introduced memory mapping in 1973, allowing two discrete sessions running concurrently, each with its own controlling terminal. 

Nova 2
The Nova 2 was essentially a simplified version of the earlier machines as increasing chip densities allowed the CPU to be reduced in size, with CPU and memory on a single board, introduced in 1973. 

Eclipse
The Eclipse line, started in 1974, had an advanced, Nova upward-compatible instruction set, and included support for virtual memory and multitasking. The line was succeeded by the [|32-bit] [|Eclipse MV] minicomputers in the early 80s, whose development was subject of [|Tracy Kidder's] book //[|The Soul of A New Machine]//. 

Nova 3
In 1975, the Nova 3 combined features from all previous Nova designs, and added a hardware stack and appropriate stack instructions. The Nova 3 was reduced to a chip set in 1976, called the microNOVA with hardware Multiply/Divide, optionally before, becoming a standard. 

Nova 4
The Nova 4 was the last of the Nova line, released in 1987, the CPU a derivation of the Eclipse S/140. The Nova 4 is implemented around four [|AMD 2901] [|bit-slice] chips and, unlike all earlier Novas, is [|microcoded].

=Chess Programs=
 * ETAOIN SHRDLU
 * Ostrich

=See also=
 * PDP-8
 * PDP-11

=External Links= > [|The best small computer in the world, 1968 - DGC.Nova] from The Computer History Museum > [|System Photographs]
 * [|Data General Nova from Wikipedia]
 * [|Data General Corporation (DG) - Nova] from The Computer History Museum
 * [|The BITSAVERS.ORG Documents Library: Data General]
 * [|Data General NOVA Basic Instruction Summary] by [|Carl R. Friend]
 * [|DG Nova Extended Instructions] by [|Carl R. Friend]
 * [|Novas Are Forever]
 * [|The Computer History Simulation Project]
 * [|DG-NOVA] by [|Ed Thelen]

SuperNOVA

 * [|Super Nova, 1970] (pdf) from The Computer History Museum

Nova 1200

 * [|The Retro-Computing Society of RI, Inc.: Nova 1200]
 * [|DG Nova 12x0s] from [|Carl Friend's] [|Minicomputer "Museum"]

Nova 8x0

 * [|840 The Loaded NOVA, 1973] (pdf) from The Computer History Museum
 * [|The Retro-Computing Society of RI, Inc.: Nova 840]
 * [|Nova 840] from [|Carl Friend's] [|Minicomputer "Museum"]

Nova 2

 * [|Data General Corp. Nova 2] from [|Carl Friend's] [|Minicomputer "Museum"]
 * [|Data General Nova 2/10] from [|The Rhode Island Computer Museum]

Eclipse

 * [|Data General Eclipse from Wikipedia]
 * [|Carl's DG Eclipse S/130] from [|Carl Friend's] [|Minicomputer "Museum"]
 * [|Carl's DG Eclispe S/140] from [|Carl Friend's] [|Minicomputer "Museum"]
 * [|Data General Eclipse S/130] from [|The Rhode Island Computer Museum]

Nova 3

 * [|DG Nova 3] from [|Carl Friend's] [|Minicomputer "Museum"]
 * [|Data General Nova-3] from [|The Rhode Island Computer Museum]
 * [|Data General Nova-3/12] from [|The Rhode Island Computer Museum]

Nova 4

 * [|Carl's DG Nova 4] from [|Carl Friend's] [|Minicomputer "Museum"]
 * [|Data General Nova 4/C and 4/X]

=References= =What links here?= include component="backlinks" page="Nova" limit="40"
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