Lab0x03

Files
file	Button.py
	Button class for detecting button actions.
file	main.py
	Contains the main finite state machine for Lab 0x03.
file	UI_front.py
	Contains the front-end User Interface for interacting with the Nucleo.

Classes
class	Button.Button
	A button class that reports precisely when it is pressed. More...
class	main.State
	A class to hold the current state of the FSM. More...

Functions
def	main.generate (time_s, data)
	Generate a CSV entry to send to the front end of the format "time, counts".
def	UI_front.main ()
	Run the frontend user interface for determining the time constant of the Nucleo's user button. More...
def	UI_front.clean_data (raw_data)
	Reformat the raw data into a list of strings. More...
def	UI_front.gen_csv (filename, data)
	Generate a .CSV file from the given data. More...
def	UI_front.calc_time_constant (times, values)
	Calculate the time constant of a button rising edge. More...
def	UI_front.gen_image (filename, data)
	Generate a plot of user button rising edge response. More...

Variables
	main.A0 = ADC(Pin.cpu.A0)
	Global A0 object for ADC counting.
string	main.START_DATA_COLLECTION = "START_DATA_COLLECTION\n".encode("ascii")
	Define a constant for data collection start.
string	main.STOP_DATA_COLLECTION = "STOP_DATA_COLLECTION\n".encode("ascii")
	Define a constant for data collection stop.
int	main.BUFF_SIZE = 5000
	Define a constant buffer size (number of data points)
int	main.SAMPLE_PERIOD = 10
	Define a constant period in microseconds (time between data points)
int	main.LOWER_THRESHOLD = 10
	Any ADC reading below this is considered LOW.
int	main.UPPER_THRESHOLD = 4000
	Any ADC reading below this is considered HIGH.
string	UI_front.START_DATA_COLLECTION = "START_DATA_COLLECTION\n".encode("ascii")
	Define a constant for data collection start.
string	UI_front.STOP_DATA_COLLECTION = "STOP_DATA_COLLECTION\n".encode("ascii")
	Define a constant for data collection stop.
bool	UI_front.UI_DEBUG = True
	set a debug flag for extra messages and buffer space

Detailed Description

Function Documentation

calc_time_constant()

def UI_front.calc_time_constant	(		times,
			values
	)

Calculate the time constant of a button rising edge.

Parameters

times	A List of time stamps in seconds, must be the same length as values
values	A List of values of ADC counts

clean_data()

def UI_front.clean_data

(

raw_data

)

Reformat the raw data into a list of strings.

Convert raw data into a friendlier format for plotting.

No longer rejects malformed data points.

Parameters

raw_data	Raw data in the form of an array.array of bytes
raw_data	A List of raw data collected from the nucleo in the form of JSON dictionaries.

Returns

A dictionary of the complete response, made of equal-length lists. Units:

• Distances [m]
• Angles [rad]
• Velocities [m/s]
• Angular Velocities [rad/s]
• Torques [N-m]

gen_csv()

def UI_front.gen_csv	(		filename,
			data
	)

Generate a .CSV file from the given data.

Parameters

filename	Filename to write the .CSV file into
data	Data (a List of strings) to write to the CSV file

gen_image()

def UI_front.gen_image	(		filename,
			data
	)

Generate a plot of user button rising edge response.

Plots Time(s) vs. Voltage (ADC counts) and reports the Time Constant

Parameters

filename	The name of the file to write plot to
data	A list of strings of the form "time,value" to be plotted

main()

def UI_front.main

(

)

Run the frontend user interface for determining the time constant of the Nucleo's user button.

Launches a terminal-based UI. If the user presses ‘G,’ the Nucleo should begin sampling data. When data collection is complete, the script generates both an image (using matplotlib) and a .CSV file of data (timestamps and data readings). The plot also reports the time constant of the rising edge. The environment variable ST_LINK must be set to the port that serial communication will be executed on.