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SWEET16 is an interpreted "byte-code" language invented by Steve Wozniak and implemented as part of the Integer BASIC ROM in the Apple II series of computers. It was created because Wozniak needed to manipulate 16-bit pointer data in his implementation of BASIC, and the Apple II was an 8-bit computer. SWEET16 code is executed as if it were running on a 16-bit processor with sixteen internal 16-bit little-endian registers, named R0 through R15. Some registers have well-defined functions:〔 * R0 is the accumulator. * R12 is the subroutine stack pointer. * R13 stores the result of all comparison operations for branch testing. * R14 is the status register. * R15 is the program counter. The 16 virtual registers, 32 bytes in total, are located in the zero page of the Apple II's real, physical memory map (at $00–$1F), with values stored as low byte followed by high byte.〔 The SWEET16 interpreter itself is located from $F689 to $F7FC in the Integer BASIC ROM. According to Wozniak, the SWEET16 implementation is a model of frugal coding, taking up only about 300 bytes in memory. SWEET16 runs about one-tenth the speed of the equivalent native 6502 code.〔 == See also == * Lazer's Interactive Symbolic Assembler — an Apple II assembler * Bytecode * Compiler * Interpreter * Interpreted language * Joel McCormack * Microsoft P-Code * Run-time system * Token threaded code * UCSD Pascal 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「SWEET16」の詳細全文を読む スポンサード リンク
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