0xB9

0xB9 is the hexadecimal representation of the byte value B9, which equals 185 in decimal. As a standalone byte, its meaning depends on the surrounding context in data or instructions.

In character encoding, 0xB9 maps to the Unicode code point U+00B9 in ISO/IEC 8859-1 (Latin-1) and Windows-1252. This code point is the superscript one character, ¹, commonly used in mathematical notation for exponents or in footnotes and ordinal indicators. The same mapping is reflected in Unicode, where U+00B9 represents the superscript one glyph, though the visible character may vary with font support.

From a numeric perspective, 0xB9 interpreted as an 8-bit value can be unsigned (185) or signed in two's complement form as -71. This dual interpretation matters when the byte is used as data versus when it is treated as a signed integer in programming languages or hardware interfaces.

In the context of x86 machine code, 0xB9 has a specific opcode meaning. It is the opcode for MOV ECX, imm32, part of the MOV r32, imm32 family that encodes a 32-bit immediate value into a 32-bit register. This makes 0xB9 a notable example of how a single byte serves as an instruction prefix in processor architectures.

Overall, 0xB9 is a common, context-dependent byte in computing, appearing in text encodings, numeric representations, and processor instructions.