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Cx51 User's Guide

Cx51 Introduction Compiling Programs Language Extensions Preprocessor Advanced Programming 8051 Derivatives Error Messages Library Reference Library Files Source Code Standard Types jmp_buf size_t va_list wchar_t Macros CBYTE CWORD DBYTE DWORD FARRAY FCARRAY FCVAR FVAR PBYTE PWORD XBYTE XWORD Routines By Category Buffer Manipulation Routines Character Routines Data Conversion Routines Intrinsic Routines Math Routines Memory Allocation Routines Stream I/O Routines String Routines Variable Length Argument Routines Miscellaneous Routines Include Files SFR Definitions 80c517.h absacc.h assert.h ctype.h float.h intrins.h limits.h math.h rtx51tny.h setjmp.h stdarg.h stddef.h stdio.h stdlib.h string.h Reference _chkfloat_ _crol_ _cror_ _getkey _irol_ _iror_ _lrol_ _lror_ _nop_ _pop_ _push_ _testbit_ _tolower _toupper abs acos acos517 asin asin517 assert atan atan2 atan517 atof atof517 atoi atol cabs calloc ceil cos cos517 cosh exp exp517 fabs floor fmod free getchar gets init_mempool isalnum isalpha iscntrl isdigit isgraph islower isprint ispunct isspace isupper isxdigit labs log log10 log10517 log517 longjmp malloc memccpy memchr memcmp memcpy memmove memset modf offsetof pow printf printf517 putchar puts rand realloc scanf scanf517 setjmp sin sin517 sinh sprintf sprintf517 sqrt sqrt517 srand sscanf sscanf517 strcat strchr strcmp strcpy strcspn strlen strncat strncmp strncpy strpbrk strpos strrchr strrpbrk strrpos strspn strstr strtod strtod517 strtok strtol strtoul switchbank tan tan517 tanh toascii toint tolower toupper ungetchar va_arg va_end va_start vprintf vsprintf Appendix

Math Routines

The math routines perform common mathematical calculations. Most of these routines work with floating-point values and include the floating-point libraries and support routines.

All of these routines are implemented as functions. Most are prototyped in the math.h include file. Functions which end in 517 (acos517, asin517, atan517, cos517, exp517, log517, log10517, sin517, sqrt517, and tan517) are prototyped in the 80c517.h include file. The rand and srand functions are prototyped in the stdlib.h include file.

The _chkfloat_, _crol_, _cror_, _irol_, _iror_, _lrol_, and _lror_ functions are prototyped in the intrins.h include file.

Routine Attributes Description
acos   Calculates the arc cosine of a specified number.
acos517   Calculates the arc cosine of a specified number.
asin   Calculates the arc sine of a specified number.
asin517   Calculates the arc sine of a specified number.
atan   Calculates the arc tangent of a specified number.
atan517   Calculates the arc tangent of a specified number.
atan2   Calculates the arc tangent of a fraction.
ceil   Finds the integer ceiling of a specified number.
cos   Calculates the cosine of a specified number.
cos517   Calculates the cosine of a specified number.
cosh   Calculates the hyperbolic cosine of a specified number.
exp   Calculates the exponential function of a specified number.
exp517   Calculates the exponential function of a specified number.
fabs reentrant Finds the absolute value of a specified number.
floor   Finds the largest integer less than or equal to a specified number.
fmod   Calculates the floating-point remainder.
log   Calculates the natural logarithm of a specified number.
log517   Calculates the natural logarithm of a specified number.
log10   Calculates the common logarithm of a specified number.
log10517   Calculates the common logarithm of a specified number.
modf   Generates integer and fractional components of a specified number.
pow   Calculates a value raised to a power.
rand reentrant Generates a pseudo random number.
sin   Calculates the sine of a specified number.
sin517   Calculates the sine of a specified number.
sinh   Calculates the hyperbolic sine of a specified number.
srand   Initializes the pseudo random number generator.
sqrt   Calculates the square root of a specified number.
sqrt517   Calculates the square root of a specified number.
tan   Calculates the tangent of a specified number.
tan517   Calculates the tangent of a specified number.
tanh   Calculates the hyperbolic tangent of a specified number.
_chkfloat_ intrinsic, reentrant Checks the status of a floating-point number.
_crol_ intrinsic, reentrnt Rotates an unsigned char left a specified number of bits.
_cror_ intrinsic, reentrant Rotates an unsigned char right a specified number of bits.
_irol_ intrinsic, reentrant Rotates an unsigned int left a specified number of bits.
_iror_ intrinsic, reentrant Rotates an unsigned int right a specified number of bits.
_lrol_ reentrant Rotates an unsigned long left a specified number of bits.
_lror_ reentrant Rotates an unsigned long right a specified number of bits.

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