Files
chest_strap/code/l452_code/packet_parser_serial.py
T

166 lines
6.2 KiB
Python

import matplotlib.pyplot as plt
import numpy as np
from scipy import signal
import time
import serial
def arr_sizes(s):
if s[-1:] != b']' or b'[' not in s:
return 1
v = int(s[s.rindex(b'[') + 1:-1])
return v
def get_type_list(ser):
ser.write(b'?')
types = []
for i in range(13):
line = ser.readline().strip(b'\n').strip(b'\r')
if line != b'':
L = line.split(b" ")
types.append({'type_name' : L[0],
'type_code' : int(L[1]),
'size' : int(L[2]),
'elements' : []
})
i = 3
while i < len(L):
types[-1]['elements'].append({'type_name' : L[i], 'name' : L[i + 1], 'offset' : int(L[i + 2]), 'n_elements' : arr_sizes(L[i + 1]), 'size' : int(L[i + 3]) * arr_sizes(L[i + 1])})
i += 4
return types
def my_filter(arr):
inds = np.where(np.abs(np.diff(arr)) > 0.005)[0]
for ind in inds:
prev_ind = ind - 1
while prev_ind in inds:
prev_ind -= 1
next_ind = ind + 1
while next_ind in inds:
next_ind += 1
arr[ind] = 0.5 * arr[prev_ind] + 0.5 * arr[next_ind]
return arr
accs = []
gyros = []
def process_imu(d, t):
global accs
global gyros
for e in t['elements']:
block = d[e['offset']:e['offset'] + e['size']]
element_size = int(len(block) / e['n_elements'])
if e['name'] == b'data[141]':
for i in range(20):
reading = block[1 + 7 * i : 8 + 7 * i]
#print(reading)
imu_reading_type = reading[0] >> 3
imu_reading_tag_cnt = (reading[0] >> 1) & 3
data = np.array([int.from_bytes(reading[2 * i + 1 : 2 * i + 3], byteorder = 'little', signed = True) for i in range(3)])
if imu_reading_type == 1:
gyros.append(250 / (1<<16) * data)
elif imu_reading_type == 2:
accs.append(4 / (1<<16) * data)
else:
assert False
if len(gyros) > 400:
gyros = gyros[-400:]
if len(accs) > 400:
accs = accs[-400:]
fig, axs = plt.subplots(2)
g = np.array(gyros)
a = np.array(accs)
axs[0].set_ylabel("dps")
axs[0].plot(g[:,0])
axs[0].plot(g[:,1])
axs[0].plot(g[:,2])
axs[1].set_ylabel("g")
axs[1].plot(a[:,0])
axs[1].plot(a[:,1])
axs[1].plot(a[:,2])
plt.savefig("acc_gyro.png")
plt.close()
def update_with_data(ser, types):
ser.timeout = 3
ser.reset_input_buffer()
start = time.time()
while(True):
ser.write(b'r')
size = int.from_bytes(ser.read(4), byteorder = 'little', signed = False)
cons = ser.read(size)
index = 0
while (index < size):
packet_type = cons[index]
t = [t for t in types if t['type_code'] == packet_type][0]
#print(index, packet_type, t['type_name'])
d = cons[index + 1 : index + 1 + t['size']]
if t['type_name'] == b'packet_imu':
process_imu(d, t)
if t['type_name'] == b'packet_msg':
print(d)
index += 1 + t['size']
# if t['type_name'] == b'packet_ekg' and e['name'] == b'readings_cnts[50]':
# chunked = [(2.4 / (1<<24)) * int.from_bytes(block[i:i + element_size], byteorder='little', signed = True) for i in range(0, len(block), element_size)]
# adcs += chunked
# if len(adcs) > 500:
# dat = np.array(adcs[-2048:])
# if len(adcs) > 2048:
# adcs = adcs[-2048:]
# #filtered_dat = my_filter(dat)
# filtered_dat = dat
# filtered_dat = signal.filtfilt(b, a, filtered_dat)
# dd = np.sort(dat)
# center = 0.5 * (dd[-100] + dd[100])
# range_ = dd[-100] - dd[100]
# if len(dat) == 2048:
# print("Freq:", 2048 / (time.time() - start))
# axs[0].cla()
# axs[1].cla()
# axs[0].set_title("ADC {:3.3f}mV".format(1000 * (range_)))
# #axs[0].plot(dat, 'r.', linestyle = '--')
# axs[0].plot(filtered_dat, 'k.', linestyle = '--')
# #axs[0].set_ylim(center - range_, center + range_)
# _fft = np.log(np.abs(np.fft.fft(filtered_dat)[1:]))
# axs[1].plot(250 * np.fft.fftfreq(dat.shape[-1])[1:], _fft, 'k.')
# axs[1].axvline(x = 60)
# plt.savefig("image.png")
# if t['type_name'] == b'packet_imu' and e['name'] == b'readings_cnts[4]':
# imu_reading_type = block[0] >> 3
# imu_reading_tag_cnt = (block[0] >> 1) & 3
# reading_xyz = [int.from_bytes(block[2:4], byteorder = 'big', signed = True),
# int.from_bytes(block[4:6], byteorder = 'big', signed = True),
# int.from_bytes(block[6:8], byteorder = 'big', signed = True)]
# if imu_reading_type == 1:
# #print("{:02x} {:d}".format(imu_reading_type, imu_reading_tag_cnt))
# gyros.append([250 * e / (1<<16) for e in reading_xyz])
# elif imu_reading_type == 2:
# accs.append([4 * e / (1<<16) for e in reading_xyz])
# else:
# print("ERR")
def main():
ser = serial.Serial(port = '/dev/ttyACM1', timeout = 0.5)
ser.flush()
ser.reset_input_buffer()
types = get_type_list(ser)
# ser.write(b'1')
# ser.write(b'3')
# ser.write(b'5')
ser.flush()
update_with_data(ser, types)
main()