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Data Types

The Cx51 Compiler provides several basic data types you may use in your C programs. The compiler supports the standard C data types as well as several data types that are unique to the Cx51 platform.

Data Types Bits Bytes Value Range
bit 1   0 to 1
signed char 8 1 -128 — +127
unsigned char 8 1 0 — 255
enum 8 / 16 1 or 2 -128 — +127 or -32768 — +32767
signed short int 16 2 -32768 — +32767
unsigned short int 16 2 0 — 65535
signed int 16 2 -32768 — +32767
unsigned int 16 2 0 — 65535
signed long int 32 4 -2147483648 — +2147483647
unsigned long int 32 4 0 — 4294967295
float 32 4 ±1.175494E-38 — ±3.402823E+38
double 32 4 ±1.175494E-38 — ±3.402823E+38
sbit 1   0 or 1
sfr 8 1 0 — 255
sfr16 16 2 0 — 65535

Note

  • The bit, sbit, sfr, and sfr16 data types are not provided in ANSI C. They are unique to the Cx51 Compiler.
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