1. dynamic update chart by matplotlib
2. raw data input by serial (COM port)
3. start/pause function for save value array
4. save as .csv format with system time as file name.
finally, it will be like this:
my Python Settings:
Install Package in Python 3.6:
from __future__ import print_function import matplotlib import matplotlib.pyplot as plt from matplotlib.gridspec import GridSpec from matplotlib.widgets import Button import numpy as np import serial import datetime import csv
STEP 0. check your COM port number at Device manager:
my MCU now is COM61
For this example, I define my MCU input in this format:
'@' (0x40) as begin, '#' (0x23) as end
5 random values from 0 to 4096 , seperated by ',' (0x2c)
and I want to dynamic show on plot
STEP 2. new Python project file, install package
at the front of this article, I post every package this project need.
from __future__ import print_function import matplotlib import matplotlib.pyplot as plt from matplotlib.gridspec import GridSpec from matplotlib.widgets import Button import numpy as np import serial import datetime import csv
STEP 3. add these file into project file path
main.py
replace
COM = 'COM61'
from __future__ import print_function import matplotlib import matplotlib.pyplot as plt from matplotlib.gridspec import GridSpec from matplotlib.widgets import Button import datetime import csv import class_serial_input as serial import class_line as line UPDATE_INTERVAL_IN_MSEC = 80 SERIAL_DATA_IN = 1 SERIAL_DATA_STOP = 0 serial_data_flag = SERIAL_DATA_IN COM = 'COM61' def start_func(label): print(" in start func") global serial_data_flag serial_data_flag = SERIAL_DATA_IN def stop_func(label): print(" in stop func") global serial_data_flag serial_data_flag = SERIAL_DATA_STOP def save_chart_csv(label): print(" save chart as csv") i_line_data = i_line.get_i_line() with open('output_%u_%u_%u_%u_%u_%u.csv' % (now_time.year, now_time.month, now_time.day, now_time.hour, now_time.minute, now_time.second), 'w', newline='') as csvfile: writer = csv.writer(csvfile, delimiter=',') writer.writerow(i_line_data) if __name__ == "__main__": print("start up \r\n") #default_port = serial_data.Serial_data("random_data" sys.argv[1]) default_port = serial.serial_input("random_data",com=COM) #init matplot interface fig = plt.figure('random serial value chart power by Agatha Kuan', figsize=(10, 8)) gs = GridSpec(14, 14, left=0.01, bottom=0.01, right=1 - 0.01, top=1 - 0.01, wspace=1, hspace=1) i_chart_axes = plt.subplot(gs[1:8, 6:14]) i_chart_axes.axis([0, 4, 0, 4096]) plt.ion() plt.ylabel("random value", color='#8d734b', size=12, family='monospace') plt.title("signal chart", color='#8d734b', size=15, family='monospace') plt.grid(True) #init line i_line = line.Init_line("line_1") #init button point_start = plt.subplot(gs[1, :4]) button_start = Button(point_start, 'start', color='0.95', hovercolor='0.6') button_start.label.set_fontsize(11) button_start.on_clicked(start_func) point_stop = plt.subplot(gs[2, :4]) button_stop = Button(point_stop, 'pause', color='0.95', hovercolor='0.6') button_stop.label.set_fontsize(11) button_stop.on_clicked(stop_func) point_save_csv = plt.subplot(gs[4, :2]) button_save_csv = Button(point_save_csv, 'save as .CSV', color='0.95', hovercolor='0.6') button_save_csv.label.set_fontsize(11) button_save_csv.on_clicked(save_chart_csv) now_time = datetime.datetime.now() sys_start_time = datetime.datetime.now() time_stamp = plt.subplot(gs[7:11, :2]) time_stamp.axis('off') time_stamp_text = plt.text(0.01, 0.05, " ", color='#8d734b', size=12, family='monospace', transform=time_stamp.transAxes) while 1 : if SERIAL_DATA_STOP != serial_data_flag: default_port.get_serial_data() i_tmp = default_port.get_data() i_line.draw_update_thershold() i_line.draw_update_signal_line(i_tmp) i_chart_axes.relim(True) i_chart_axes.autoscale_view(True, 'y', True) now_time = datetime.datetime.now() time_stamp_text.set_text("start at %u/%u %u:%u:%u \n\n" "System Time %u/%u %u:%u:%u \n"%(sys_start_time.month,sys_start_time.day,sys_start_time.hour, sys_start_time.minute,sys_start_time.second, now_time.month, now_time.day,now_time.hour, now_time.minute, now_time.second)) fig.canvas.draw() plt.pause(float(UPDATE_INTERVAL_IN_MSEC) / 1000.0) default_port.clear_data()
class_serial_input.py
import serial import numpy as np POINT_TO_UPDATE = 5 SEPERATE_SIGN = 0x2C DATA_MAX_LEN = (2+(1+4)*(POINT_TO_UPDATE+1))*2 __metaclass__ = type class serial_input: def __init__(self,name,com='COM61',baudrate=115200): self.ser = serial.Serial(com, baudrate) self.port = com self.baudrate = baudrate self.num_array = np.repeat(0x00, POINT_TO_UPDATE) def get_serial_data(self): self.ser.flushInput() char_in = self.ser.read(DATA_MAX_LEN) char_in = bytearray(char_in) temp = np.repeat(0x00, DATA_MAX_LEN) valid_tmp = np.repeat(0x00, DATA_MAX_LEN) for i in range (DATA_MAX_LEN): temp[i] = int(char_in[i]) start_addr = np.argwhere(temp == 0x40) end_addr = np.argwhere(temp == 0x23) if(int(start_addr[0]) < int(end_addr[0])): start = int(start_addr[0]) end = int(end_addr[0]) for i in range (end-start): valid_tmp[i] = temp[start+1+i] else: start = int(start_addr[0]) end = int(end_addr[1]) for i in range(end - start): valid_tmp[i] = temp[start + 1 + i] common_addr = np.argwhere(valid_tmp == 0x2c) for i in range (int(common_addr[0])): self.num_array[0] = self.num_array[0]+(valid_tmp[i]-0x30)*pow(10, int(common_addr[0])-1-i) for i in range(1,4): start = int(common_addr[i-1]) end = int(common_addr[i]) for j in range(0,end-start-1): self.num_array[i] = self.num_array[i] + (valid_tmp[start+1+j]-0x30)*pow(10,end-start-2-j) end_addr = np.argwhere(valid_tmp == 0x23) for i in range (int(end_addr[0])-int(common_addr[3])-1): self.num_array[4] = self.num_array[4]+(valid_tmp[int(common_addr[3])+1+i]-0x30)*pow(10, int(end_addr[0])-int(common_addr[3])-2-i) def get_data(self): print(self.num_array) return self.num_array def clear_data(self): self.num_array = np.repeat(0x00, POINT_TO_UPDATE)
class_line.py
#線條的顏色: https://www.cnblogs.com/darkknightzh/p/6117528.html import matplotlib.pyplot as plt import numpy as np __metaclass__ = type THRESHOLD_VALUE = 2000 TIME_WINDOW_WIDTH_IN_SEC = 2.0 POINTS_IN_ONE_UPDATE = 5 VIEW_POINT_IN_SEC = 1*POINTS_IN_ONE_UPDATE TIME_STAMP_ARRAY = np.arange(0, VIEW_POINT_IN_SEC, 1) class Init_line: def __init__(self,name): global TIME_STAMP_ARRAY self.time_window_begin = 0.0 self.time_window_end = self.time_window_begin + TIME_WINDOW_WIDTH_IN_SEC self.time_line_value = TIME_STAMP_ARRAY self.thershold_line_value = np.repeat(THRESHOLD_VALUE, len(self.time_line_value)) freq = 5.0 omega = 2.0 * np.pi * freq constant_for_signal_shift = 1 self.i_raw_line_value = np.sin(omega * self.time_line_value) + constant_for_signal_shift self.thershold_line, = plt.plot(self.time_line_value, self.thershold_line_value,label="thershold",color='#0080FF') self.i_raw_line, = plt.plot(self.time_line_value, self.i_raw_line_value,label="I raw", color='#FF8000') plt.legend(loc='upper right') def draw_thershold(self): self.thershold_line, = plt.plot(self.time_line_value, self.thershold_line_value) def draw_update_thershold(self): global TIME_STAMP_ARRAY self.time_line_value = TIME_STAMP_ARRAY self.thershold_line.set_data(self.time_line_value, self.thershold_line_value) def draw_init_signal_line(self): self.i_raw_line, = plt.plot(self.time_line_value, self.i_raw_line_value) def draw_update_signal_line(self,update_i_temp): self.i_raw_line_value = np.roll(self.i_raw_line_value, -POINTS_IN_ONE_UPDATE) self.i_raw_line_value[-(POINTS_IN_ONE_UPDATE):] = update_i_temp self.i_raw_line.set_data(self.time_line_value, self.i_raw_line_value) def get_i_line(self): return self.i_raw_line_value
STEP 4.run the Python file
when you run this python script, the PLOT start to update.
STEP 5. SAVE as csv file with time stamp as file name
press pause button to pause the update plot, then
press save as csv button
you will see a csv file in project path with time stamp as file name
open the file in EXCEL, you can see the raw data:
NOTE:
- this implement only use matplotlib to draw figure and canvas, didn't use other graphic UI structure like TKinter or PyQT5
- the speed of COM data update is limited cause I didn't use multi-thread programming.
reference:
- https://www.cnblogs.com/darkknightzh/p/6117528.html
- https://zhuanlan.zhihu.com/p/32019813
- https://tw.saowen.com/a/aeeef5a75c5a3589f64d9f31953295c1b21a60ff72902f6e93f16327be2d3d78
