- PyBoard V1.1
uPython V1.2
Python V3.8
The instructions I send from the PC (using python 3.8) take the form of a list of ints (each int is between 0 and 255) which is then converted into a bytearray before been transmitted via a com port. I know that the bytearray conversion of the list can produce some unexpected representations for the individual ints such as 10 becoming ‘n’ and 9 becoming ‘t’, however these convert back to the original int on the PyBoard when required.
Is the number 3 or its bytearray representation of \x03 a special command/escape character/reserved byte on the PyBoard V1.1 or should I be able to transmit it without any issue? Ideally I would like to be able to use all numbers in the range of 0 to 255 for each int in the instruction list.
Below I have included a copy of the python (running on PC) and uPython code used when encountering this error. I can upload some copies of the different outputs from my python console showing the different behaviours triggered by the number 3 if it will help. The list a is the list of ints sent from the PC to the PyBoard.
uPython Code running on PyBoard
Code: Select all
# main.py -- put your code here
import pyb
usb = pyb.USB_VCP()
def function_sort(z):
del z[0]
if z[0] == 1:
flash_LED(z)
elif z[0] == 2:
print_string(z)
else:
usb.write("instruction not identified\r\n")
def flash_LED(z):
count = z[1]
i = 0
while i < count:
pyb.LED(1).on()
pyb.delay(1000)
pyb.LED(3).on()
pyb.delay(1000)
pyb.LED(1).off()
pyb.delay(500)
pyb.LED(3).off()
pyb.delay(500)
i += 1
def print_string(z):
if z[1] == 1:
usb.write("string 1\r\n")
elif z[1] == 2:
usb.write("string 2\r\n")
elif z[1] == 3:
usb.write("string 3\r\n")
else:
usb.write("string not found \r\n")
usb.write("starting while loop\r\n")
while True:
if usb.any():
usb.write("data on serial buffer\r\n")
a = usb.read()
usb.write(a)
b = []
for i in a:
b.append(i)
#usb.write(i)
usb.write("data moved from buffer to list\r\n")
usb.write(bytes(b))
c = b[0]
usb.write(bytes(c))
usb.write("\r\n")
d = b[0:c]
usb.write("instruction taken from buffer for sorting\r\n")
function_sort(d)
usb.write("instruction sorted and appropriate action taken\r\n")
pyb.LED(2).on()
pyb.delay(500)
pyb.LED(2).off()
pyb.delay(500)
pyb.LED(2).on()
pyb.delay(500)
pyb.LED(2).off()
pyb.delay(500)
pyb.LED(4).on()
pyb.delay(1000)
pyb.LED(4).off()
pyb.delay(1000)Code: Select all
#-*-coding; utf-8 -*-
"""
Created on Tue Sep 8 17:08:30 2020
@author:
the script
"""
import serial
import time
if 'ser' in locals():
ser.close()
del ser
ser = serial.Serial(port ='COM42', baudrate=9600, timeout=None)
ser.reset_input_buffer()
ser.reset_output_buffer()
a = [4,1,5,4,7,2,2,5,2,2,3] #the list used to transmit the instructions
#message = a
message = bytearray(a)
print(message)
ser.write(message)
ser.reset_input_buffer()
ser.reset_output_buffer()
"""
below reads from com port to recive output from pyboard
"""
y = 0
x = []
z = []
print("entering while loop")
g = 0
while True:
waiting = ser.in_waiting
if waiting > 0:
x=ser.readline()
print(x)
g = 0
if waiting == 0:
g +=1
time.sleep(0.01)
if g > 500:
break
ser.reset_output_buffer()
ser.reset_input_buffer()
print(ser.name)
ser.close()