I am new to Pyserial, I'm trying to use it for communication between my computer and a microcontroller, I need to receive the data and put it into variables so that I can plot with those variables. Is there any way to do this? I have currently figured out reading data from input signals.
import serial
import sys
import Queue
import threading
ser = serial.Serial(port='COM6',timeout=None, baudrate= 57600)
# opening the port 'ser' that was just created to receive data
flag = ser.isOpen()
print flag
while 1:
data = ser.read(1)
n = ser.inWaiting()
if n:
data = data + ser.read(n)
data = data.split()
for item in data:
item = str(item)
sys.stdout.write(item + '\n')
I'm doing it like the following: to transfer data to and fro my AVR and Beagle running UBuntu.
serial = serial.Serial("/dev/ttyO1", baudrate=9600)
then after opening the serial port at a particualr set baudrate you just need to:
while True:
while serial.inWaiting() > 0:
inChar = serial.read() # Read a character inChar has that byte what is sent over the UART
and to send over to the microcontroller just do serial.write("") that's it.
but make sure while you do all these commands the serial line is open()
Related
I have a Spektrum Radio transmitter, along with its receiver. What I am currently trying to do is by using microPython and a Raspberry Pi Pico, I want to read the data coming into the receiver, and convert that into servo commands. All I know is that the protocol used by the transmitter/receiver is DSMX. How can I go about doing this? I only need to receive, I don't need to transfer any data back from the Raspberry Pi Pico.
I'm using Thonny, and all I've done is try to use the UART module and ustruct module and create a variable using that
uart = UART(1, baudrate = 115200)
data = uart.read()
header,id,data,error_checking,trailer = ustruct.unpack('>BBHHB',data)
When trying to run this, I get thrown the error
TypeError: object with buffer protocol required
I didn't expect anything, as I don't really know what I'm doing.
Any help would be really appreciated.
You're getting that TypeError exception because your call to uart.read() is returning None (meaning that there was no data available on the serial port). I don't know anything about the DSMX protocol, but to avoid that error in your code you probably want something like:
format = 'BBHHB'
required_size = ustruct.calcsize(format)
if uart.any() >= required_size:
data = uart.read(required_size)
header,id,data,error_checking,trailer = ustruct.unpack(f'>{format}',data)
...and the above probably needs to live in some sort of loop.
I have looked everywhere on the internet, sadly i couldn't find anything. Is there anyway i could read data from my computer to the raspberry pi pico running micropython? Any help would be appreciated. I use pyserial to send and receive data on my computer.
I also had this issue and from this link I was able to figure it out. To read data from the usb port use "sys.stdin.buffer.read(8)".
Here is a short code that you can upload to the pico to do this.
import time
import sys
while True:
print("hello")
data = sys.stdin.buffer.read(8)
# to convert to string use data = sys.stdin.buffer.read(8).decode("utf-8")
print(data)
time.sleep(1)
With this code it will wait until 8 bytes come in, until then it will idle. I'm sure there is a way around it, just haven't tried yet.
I used the Arduino IDE serial monitor to send data. Upload this code in Thonny (save it as main.py so it starts on power up), then disconnect the pico, plug it back in, and open the Arduino serial monitor. Send something like '12345678' and it should spit it back out.
EDIT:
The above code will idle until you send it data. To have the pico continue running if no data is sent, use the following (source):
import time
import sys
import select
while True:
print("hello")
res = select.select([sys.stdin], [], [], 0)
data = ""
while res[0]:
data = data + sys.stdin.read(1)
res = select.select([sys.stdin], [], [], 0)
print(data, end = "")
time.sleep(1)
And you can just use Thonny to send the data, you don't need the Arduino IDE.
First off. This is not in any way a class assignment. This is my own personal work and research. I just want to get that out of the way.
I am learning how to use Matlab with various Arduino projects. I am a seasoned Matlab user but I am fairly new to the entire Arduino space.
I am trying to send some numerical data from Matlab (via a GUI) to my Arduino Uno and have the Arduino write it to my micro SC card. This is a temporary step to my larger project. However, there is no need to go into those specifics as they are outside of the scope of my issues.
I am fairly confident that the Matlab code works and the Arduino code is slightly modified from another project I did where I wrote and read random numbers from my micro SD card.
However, as I run the Matlab code, the Arduino blinks as if it is receiving the data but after I check the micro SD card it remains blank.
I am confident that my Arduino is wired correctly to my micro SD card adapter since this remains the same from my prior project.
Therefore, I am sure I am missing something trivial to get it to work.
I have researched several websites on the subject and their method and mine seem to align very well.
I am fairly certain the problem is in the conditional statement:
if (Serial.available() > 0) {
As you will see.
The Matlab code is below:
arduinoCom = serial('COM3', 'BaudRate', 115200);
sendData = 5;
fopen(arduinoCom);
fprintf(arduinoCom,'%i',sendData); %this will send 5 to the arduino
fclose(arduinoCom);
delete(arduinoCom);
The Arduino code is as follows:
#include <SD.h> // load SD library
int chipSelect = 4; // Chip select pin for the MicroSD Card Adapter
int incomingByte = 0; // for incoming serial data.
File SDF; // Serial data received is saved here.
void setup() {
Serial.begin(115200); // start serial connection to print out debug messages and data
pinMode(chipSelect, OUTPUT); // chip select pin must be set to OUTPUT mode
while (!Serial) {
}
}
void loop() {
// Open file, Write data, Close file only when you receive data
if (Serial.available() > 0) {
incomingByte = Serial.read();
SDF = SD.open("SerialDataFile.txt", FILE_WRITE); // open "SerialDataFile.txt" to write data
SDF.println(incomingByte, DEC); // write ASCII-encoded decimal number to file
SDF.close(); // close file
}
}
The expected result would be a file "SerialDataFile.txt" stored on my micro SD card with the value 5.
Thank you for your help!
i have an output from serial arduino like this on raspberry
30.27|34.00\n
30.27|32.00\n
30.21|33.00\n
code on raspberry:
import serial
ser = serial.Serial('/dev/ttyACM0', 9600)
while 1 :
ser.readline()
i want to spit like this
x=30.21
y=33.00
is this possible if data send in real time,
thanks..
Using the same code you already have, try:
import serial
ser = serial.Serial('/dev/ttyACM0', 9600)
while 1 :
data=ser.readline()
x=data.split("|")[0]
y=data.split("|")[1]
print "x=",x
print "y=",y
You can streamline the code some more but wanted to make it step by step for easier reading.
I've connected my smart meter with a serial cable. However, when retrieving the data using PySerial I always get these lines:
b'\x00\n'
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
\x00\x00\x00\x00\x00\x00\x00\x00
Eventually, I do get some data, but not even all.
Output should be like:
/ISk5\2ME382-1003
0-0:96.1.1(4B414C37303035313039)
1-0:1.8.1(00180.724*kWh)
1-0:1.8.2(00001.416*kWh)
1-0:2.8.1(00000.000*kWh)
1-0:2.8.2(00000.000*kWh)
[...]
!
My script:
import sys
import serial
ser = serial.Serial()
ser.baudrate = 9600
ser.bytesize=serial.SEVENBITS
ser.parity=serial.PARITY_EVEN
ser.stopbits=serial.STOPBITS_ONE
ser.xonxoff=0
ser.rtscts=0
ser.timeout=None
ser.port="/dev/ttyUSB0"
ser.open()
count=0
stack=[]
while count < 25:
p1_raw = str(ser.readline())
print(p1_raw)
count=count+1
ser.close()
exit
The problem seems to be with Python/PySerial. When using cu or minicom the data is received properly.
Any ideas?
After trying various settings, this seems to have solved the problem:
ser.xonxoff=1