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Nova
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a [https://en.wikipedia.org/wiki/16-bit 16-bit] [https://en.wikipedia.org/wiki/Minicomputer minicomputer] series built by the American company [https://en.wikipedia.org/wiki/Data_General Data General] starting in 1968. The Nova was designed by [[Digital Equipment Corporation|DEC]] [[PDP-8]] chief engineer and Data General co-founder [https://en.wikipedia.org/wiki/Edson_de_Castro Edson de Castro]. It was packaged into a single [https://en.wikipedia.org/wiki/19-inch_rack rack mount] case.
Unlike the [[PDP-8]], Nova was a [https://en.wikipedia.org/wiki/Load/store_architecture load/store architecture]. It had four 16-bit [https://en.wikipedia.org/wiki/Accumulator_%28computing%29 accumulators], where two could be used as [https://en.wikipedia.org/wiki/Index_register index registers], and a 15-bit [https://en.wikipedia.org/wiki/Address_space address space] and [https://en.wikipedia.org/wiki/Program_counter PC]. The Nova is a [[Big-endian|big-endian]] architecture. Since there is no [[Byte|byte]] addressing, bytes need to be parsed out of [[Word|words]] using swaps and masks high-order byte first <ref>[http://users.rcn.com/crfriend/museum/doco/DG/Nova/ Data General NOVA Basic Instruction Summary] by [http://users.rcn.com/crfriend/ Carl R. Friend]</ref>. Nova consists of a [[Nibble|nibble]]-serial 4-bit [[Combinatorial Logic#ALU|ALU]] - its [https://en.wikipedia.org/wiki/Reduced_instruction_set_computing 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 8K [[Word|words]] of [[Memory#Core|magnetic core memory]].
[https://en.wikipedia.org/wiki/System_software System software] provided include the [https://en.wikipedia.org/wiki/Real-time_operating_system real time operating system] [https://en.wikipedia.org/wiki/Data_General_RDOS RDOS], [[Assembly|assembler]], [[Basic]] interpreter, and [[Fortran]] and [[Algol]] compiler, expanded with [[Forth]], [[Lisp]], and [[C]] through third party vendors <ref>[https://en.wikipedia.org/wiki/Data_General_Nova Data General Nova from Wikipedia]</ref>.
[[FILE:Nova1200.agr.jpg|border|right|thumb| Nova 1200 Front panel <ref>Front panel of a Data General Nova 1200 minicomputer by [https://commons.wikimedia.org/wiki/User:ArnoldReinhold Arnold Reinhold], [https://creativecommons.org/licenses/by-sa/4.0/ CC BY-SA 4.0], [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons], [https://en.wikipedia.org/wiki/Data_General_Nova Data General Nova from Wikipedia], bit 0 for Carry, bit 1 for MSB and bit 15 for LSB!</ref> ]]
The Nova 1200 contained the entire CPU one one board, first shipped in 1971 <ref>[http://www.rcsri.org/collection/nova-1200/ The Retro-Computing Society of RI, Inc.: Nova 1200]</ref>. It still had the [[Nibble]]-serial ALU, and up to 32 Kibi 32K words [[Memory#Core|magnetic core memory]].
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==Nova 8x0==
