Learn how to interface arduino through serial communication with python using the pyduino library. There are few other tutorials out there on instructables on how to interface arduino with python but they don't show you how to do everything, where hopefully this tutorial will give you a foundation for creating more advanced arduino projects with the pyduino library. For a basic overview on how serial communication works between arduino and python check out http://playground.arduino.cc/interfacing/python. Before we begin let me inform you on some of the limitations that python has when creating arduino projects. Python does not create arduino sketches, nor are you going to be uploading more than 1 sketch to your board this entire time. Instead, python is going to be sending small strings (only a few chars) to our arduino board, our arduino board will have a preloaded sketch associated with the pyduino library to interpret our small message then perform said task.
Requirements:
Arduino Uno
1 LED
This library make it easy to add support for different Bluetooth services like a PS3 or a Wii controller or SPP which is a virtual serial port via Bluetooth. Some different examples can be found in the example directory. Now that the library is installed, an example sketch can be found in the ‘Examples’ submenu. Example Sketch. Since this is a relatively new feature of the Arduino IDE at the time of this writing not all SparkFun products will have libraries in the library manager. Arduino and Processing. Processing is an open source language/ development tool for writing programs in other computers. Useful when you want those other computers to 'talk' with an Arduino, for instance to display or save some data collected by the Arduino. SoftwareSerial Library. The Arduino hardware has built-in support for serial communication on pins 0 and 1 (which also goes to the computer via the USB connection). The native serial support happens via a piece of hardware (built into the chip) called a UART. This hardware allows the Atmega chip to receive serial communication even while. Library Manager The Library Manager is a newer feature of the Arduino IDE. Many of the popular libraries, including most of Adafruit's, are in the Library Manager. There are several functions offered by ESP8266’s SDK and not present in Arduino WiFi library. If such function does not fit into one of classes discussed above, it will likely be in Generic Class. For additional details regarding diagnostics using serial ports please refer to the documentation.
1 Photoresistor
1 10k ohm Resistor
1 Resistor, anything between 220 ohm and 1k ohm
Wires
Breadboard
Arduino USB cable
Computer
Python Dependencies:
Python
pySerial ( $pip install pyserial )
pyduino library ( will be supplied in tutorial )
Steps:
Create our arduino circuit
Set up the Pyduino Library
Set up our arduino sketch
Create our first blinking pyduino script
- Arduino Tutorial
- Arduino Function Libraries
- Arduino Advanced
- Arduino Projects
- Arduino Sensors
- Motor Control
- Arduino And Sound
- Arduino Useful Resources
- Selected Reading
Arduino Library Files
The Arduino Math library (math.h) includes a number of useful mathematical functions for manipulating floating-point numbers.
Library Macros
Following are the macros defined in the header math.h −
Macros | Value | Description |
---|---|---|
M_E | 2.7182818284590452354 | The constant e. |
M_LOG2E | 1.4426950408889634074 /* log_2 e */ | The logarithm of the e to base 2 |
M_1_PI | 0.31830988618379067154 /* 1/pi */ | The constant 1/pi |
M_2_PI | 0.63661977236758134308 /* 2/pi */ | The constant 2/pi |
M_2_SQRTPI | 1.12837916709551257390 /* 2/sqrt(pi) */ | The constant 2/sqrt(pi) |
M_LN10 | 2.30258509299404568402 /* log_e 10 */ | The natural logarithm of the 10 |
M_LN2 | 0.69314718055994530942 /* log_e 2 */ | The natural logarithm of the 2 |
M_LOG10E | 0.43429448190325182765 /* log_10 e */ | The logarithm of the e to base 10 |
M_PI | 3.14159265358979323846 /* pi */ | The constant pi |
M_PI_2 | 3.3V1.57079632679489661923 /* pi/2 */ | The constant pi/2 |
M_PI_4 | 0.78539816339744830962 /* pi/4 */ | The constant pi/4 |
M_SQRT1_2 | 0.70710678118654752440 /* 1/sqrt(2) */ | The constant 1/sqrt(2) |
M_SQRT2 | 1.41421356237309504880 /* sqrt(2) */ | The square root of 2 |
acosf | - | The alias for acos() function |
asinf | - | The alias for asin() function |
atan2f | - | The alias for atan2() function |
cbrtf | - | The alias for cbrt() function |
ceilf | - | The alias for ceil() function |
copysignf | - | The alias for copysign() function |
coshf | - | The alias for cosh() function |
expf | - | The alias for exp() function |
fabsf | - | The alias for fabs() function |
fdimf | - | The alias for fdim() function |
floorf | - | The alias for floor() function |
fmaxf | - | The alias for fmax() function |
fminf | - | The alias for fmin() function |
fmodf | - | The alias for fmod() function |
frexpf | - | The alias for frexp() function |
hypotf | - | The alias for hypot() function |
INFINITY | - | INFINITY constant |
isfinitef | - | The alias for isfinite() function |
isinff | - | The alias for isinf() function |
isnanf | - | The alias for isnan() function |
ldexpf | - | The alias for ldexp() function |
log10f | - | The alias for log10() function |
logf | - | The alias for log() function |
lrintf | - | The alias for lrint() function |
lroundf | - | The alias for lround() function |
Arduino Softwareserial Download
Library Functions
The following functions are defined in the header math.h −
S.No. | Library Function & Description |
---|---|
1 | double acos (double __x) The acos() function computes the principal value of the arc cosine of __x. The returned value is in the range [0, pi] radians. A domain error occurs for arguments not in the range [-1, +1]. |
2 | double asin (double __x) The asin() function computes the principal value of the arc sine of __x. The returned value is in the range [-pi/2, pi/2] radians. A domain error occurs for arguments not in the range [-1, +1]. |
3 | double atan (double __x) The atan() function computes the principal value of the arc tangent of __x. The returned value is in the range [-pi/2, pi/2] radians. |
4 | double atan2 (double __y, double __x) The atan2() function computes the principal value of the arc tangent of __y / __x, using the signs of both arguments to determine the quadrant of the return value. The returned value is in the range [-pi, +pi] radians. |
5 | double cbrt (double __x) Microsoft office access 2003 indir sp3. The cbrt() function returns the cube root of __x. |
6 | double ceil (double __x) The ceil() function returns the smallest integral value greater than or equal to __x, expressed as a floating-point number. |
7 | static double copysign (double __x, double __y) The copysign() function returns __x but with the sign of __y. They work even if __x or __y are NaN or zero. |
8 | double cos(double __x) The cos() function returns the cosine of __x, measured in radians. |
9 | double cosh (double __x) The cosh() function returns the hyperbolic cosine of __x. |
10 | double exp (double __x) The exp() function returns the exponential value of __x. |
11 | double fabs (double __x) The fabs() function computes the absolute value of a floating-point number __x. |
12 | double fdim (double __x, double __y) The fdim() function returns max(__x - __y, 0). If __x or __y or both are NaN, NaN is returned. |
13 | double floor (double __x) The floor() function returns the largest integral value less than or equal to __x, expressed as a floating-point number. |
14 | double fma (double __x, double __y, double __z) The fma() function performs floating-point multiply-add. This is the operation (__x * __y) + __z, but the intermediate result is not rounded to the destination type. This can sometimes improve the precision of a calculation. |
15 | double fmax (double __x, double __y) The fmax() function returns the greater of the two values __x and __y. If an argument is NaN, the other argument is returned. If both the arguments are NaN, NaN is returned. |
16 | double fmin (double __x, double __y) The fmin() function returns the lesser of the two values __x and __y. If an argument is NaN, the other argument is returned. If both the arguments are NaN, NaN is returned. |
17 | double fmod (double __x, double__y) The function fmod() returns the floating-point remainder of __x / __y. |
18 | double frexp (double __x, int * __pexp) The frexp() function breaks a floating-point number into a normalized fraction and an integral power of 2. It stores the integer in the int object pointed to by __pexp. If __x is a normal float point number, the frexp() function returns the value v, such that v has a magnitude in the interval [1/2, 1) or zero, and __x equals v times 2 raised to the power __pexp. If __x is zero, both parts of the result are zero. If __x is not a finite number, the frexp() returns __x as is and stores 0 by __pexp. Note − This implementation permits a zero pointer as a directive to skip a storing the exponent. |
19 | double hypot (double __x, double__y) The hypot() function returns sqrt(__x*__x + __y*__y). This is the length of the hypotenuse of a right triangle with sides of length __x and __y, or the distance of the point (__x, __y) from the origin. Using this function instead of the direct formula is wise, since the error is much smaller. No underflow with small __x and __y. No overflow if result is in range. |
20 | static int isfinite (double __x) The isfinite() function returns a nonzero value if __x is finite: not plus or minus infinity, and not NaN. |
21 | int isinf (double __x) The function isinf() returns 1 if the argument __x is positive infinity, -1 if __x is negative infinity, and 0 otherwise. Note − The GCC 4.3 can replace this function with inline code that returns the 1 value for both infinities (gcc bug #35509). |
22 | int isnan (double __x) The function isnan() returns 1 if the argument __x represents a 'not-a-number' (NaN) object, otherwise 0. |
23 | double ldexp (double __x, int __exp ) The ldexp() function multiplies a floating-point number by an integral power of 2. It returns the value of __x times 2 raised to the power __exp. |
24 | double log (double __x) The log() function returns the natural logarithm of argument __x. |
25 | double log10(double __x) The log10() function returns the logarithm of argument __x to base 10. |
26 | long lrint (double __x) The lrint() function rounds __x to the nearest integer, rounding the halfway cases to the even integer direction. (That is both 1.5 and 2.5 values are rounded to 2). This function is similar to rint() function, but it differs in type of return value and in that an overflow is possible. Returns The rounded long integer value. If __x is not a finite number or an overflow, this realization returns the LONG_MIN value (0x80000000). |
27 | long lround (double __x) The lround() function rounds __x to the nearest integer, but rounds halfway cases away from zero (instead of to the nearest even integer). This function is similar to round() function, but it differs in type of return value and in that an overflow is possible. Returns The rounded long integer value. If __x is not a finite number or an overflow was, this realization returns the LONG_MIN value (0x80000000). |
28 | double modf (double __x, double * __iptr ) The modf() function breaks the argument __x into integral and fractional parts, each of which has the same sign as the argument. It stores the integral part as a double in the object pointed to by __iptr. The modf() function returns the signed fractional part of __x. Note − This implementation skips writing by zero pointer. However, the GCC 4.3 can replace this function with inline code that does not permit to use NULL address for the avoiding of storing. |
29 | float modff (float __x, float * __iptr) The alias for modf(). |
30 | double pow (double __x, double __y) The function pow() returns the value of __x to the exponent __y. |
31 | double round (double __x) The round() function rounds __x to the nearest integer, but rounds halfway cases away from zero (instead of to the nearest even integer). Overflow is impossible. Returns The rounded value. If __x is an integral or infinite, __x itself is returned. If __x is NaN, then NaN is returned. |
32 | int signbit (double __x) The signbit() function returns a nonzero value if the value of __x has its sign bit set. This is not the same as `__x < 0.0', because IEEE 754 floating point allows zero to be signed. The comparison `-0.0 < 0.0' is false, but `signbit (-0.0)' will return a nonzero value. |
33 | double sin (double __x) The sin() function returns the sine of __x, measured in radians. |
34 | double sinh (double __x) The sinh() function returns the hyperbolic sine of __x. |
35 | double sqrt (double __x) The sqrt() function returns the non-negative square root of __x. |
36 | double square (double __x) The function square() returns __x * __x. Note − This function does not belong to the C standard definition. |
37 | double tan (double __x) The tan() function returns the tangent of __x, measured in radians. |
38 | double tanh ( double __x) The tanh() function returns the hyperbolic tangent of __x. |
39 | double trunc (double __x) The trunc() function rounds __x to the nearest integer not larger in absolute value. |
Example
The following example shows how to use the most common math.h library functions −