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Наткнулся на интересную статью про интереснейший агрегат 90-х - AT&T EO Personal Communicator, построенный на чудо-процессоре - Hobbit с архитектурой CRISP – C-language Reduced Instruction Set Processor (процессор с сокращенным набором команд языка Си).

"... Что же представлял собой AT&T EO Personal Communicator? Если вкратце, то вариант современного планшетного компьютера, собранный по технологиям 90-х. Нынешние планшетники характеризуются наличием большого сенсорного экрана, беспроводными коммуникациями (Wi-Fi, Bluetooth, 3G), базовым набором предустановленных приложений (календарь, блокнот, почтовый клиент и т.д.), возможностью подключения к облачным сервисам и специальной версией операционной системы. Так вот, персональный коммуникатор EO обладал всеми этими признаками! Естественно, в контексте возможностей техники двадцатилетней давности... "

Статья: http://www.mobi.ru/News/13026/ATT_EO_Pe ... vremya.htm
Википедия: http://en.wikipedia.org/wiki/AT%26T_Hobbit

Еще несколько строк:
AT&T CRISP/Hobbit, CISC amongst the RISC (1987)

The AT&T Hobbit ATT92010 (around 1992) was a commercial version of the CRISP processor, inspired by the Bell Labs C Machine project, aimed at a design optimised for the C language (designed in part by David Ditzel, who later worked on the 64-bit SPARC, and later the AMD 29000 (in Hobbit it's much smaller (64 32-bit words) but is easily expandable), and Hobbit has no global registers. Addresses can be memory direct or indirect (for pointers) relative to the stack pointer without extra instructions or operand bits. The cache is not optimised for multiprocessors.
Hobbit has an instruction prefetch buffer (3K in 92010, 6K in the 92020), like the 8086, but decodes the variable length (1, 3 or 5 halfword (16 bit)) instructions into a thirty-two entry instruction cache. Branches are not delayed, and a prediction bit directs speculative branch execution. The decode unit folds branches into the decoded instructions (which include next and alternate next PC), so a predicted branch does not take any clock cycles. The three stage execution unit takes instructions from the decode cache. Results can be forwarded when available to any prior stage as needed.

Though CISC in philosophy, the Hobbit is greatly simplified compared to traditional memory-data designs, and features some very elegant design features. AT&T prefers to call it a RISC processor, and performance is comparable to similar load-store designs such as the ARM. Its most prominent use was in the EO Personal Communicator, a competitor to Apple's Newton which used the ARM processor, as well as a prototype development machine for BeOS. The product and name were discontinued.

As an aside, the complexity in making a stack-based CPU fast led fellow AT&T researchers working on the Inferno operating system to decide on a register based virtual machine, rather than stack-based like Sun Java and Microsoft .NET IL.

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щас, мне кажется, такое не прокатит...