GNU Radio Companion 3.10.4.0 (Windows - Radioconda installer)
Arduino Uno
WL101-341 OOK/ASK receiver
PySerial 3.5 + Python 3.11.4

I copied pyserial-3.5.dist-info and serial folders from Python 3.11.4 to
C:\Users\<user>\radioconda\Lib\site-packages

Embedded Python block code
 

import numpy as np
import serial
from gnuradio import gr

class blk(gr.sync_block):  # other base classes are basic_block, decim_block, interp_block

    def __init__(self, comPort='COM5', comSpeed=38400.0, timeout=2):
        gr.sync_block.__init__(
            self,
            name='window voltage',
            in_sig=None,
            out_sig=[np.byte]
        )
        self.comPort = comPort
        self.comSpeed = comSpeed
        self.ser = serial.Serial(self.comPort, self.comSpeed)
        print(self.ser)

    def work(self, input_items, output_items):
        d = self.ser.read(64)
        i = 0
        for b in d:
           output_items[0][i] = b
           i = i + 1
        return len(output_items[0])

Arduino code

#define DATA_PIN      2

#define SERIAL_SPEED  38400

#define DATA_SIZE     64

 

#define pinOfPin(P)\

  (((P)>=0&&(P)<8)?&PIND:(((P)>7&&(P)<14)?&PINB:&PINC))

#define pinIndex(P)((uint8_t)(P>13?P-14:P&7))

#define pinMask(P)((uint8_t)(1<<pinIndex(P)))

 

#define isHigh(P)((*(pinOfPin(P))& pinMask(P))>0)

#define isLow(P)((*(pinOfPin(P))& pinMask(P))==0)

#define digitalState(P)((uint8_t)isHigh(P))

 

uint8_t data_1[DATA_SIZE];

uint8_t data_2[DATA_SIZE];

uint8_t buf_num = 1;

 

volatile uint8_t index = 0;

volatile bool sendData = false;

 

void setup() {

  Serial.begin(SERIAL_SPEED);

  pinMode(DATA_PIN, INPUT);

  memset(data_1, 0, sizeof(data_1));

  memset(data_2, 0, sizeof(data_2));

  attachInterrupt(digitalPinToInterrupt(DATA_PIN), isr, CHANGE);

}

 

void loop() {

  if (sendData) {

    index = 0;

    if (buf_num) {

      buf_num = 0;

      sendData = false;

      Serial.write(data_1, DATA_SIZE);

    }

    else {

      buf_num = 1;

      sendData = false;

      Serial.write(data_2, DATA_SIZE);

    }

  }

}

 

void isr() {

  static uint8_t p = 0;

  static uint8_t v = 0;

  if (!sendData) {

    // msbfirst (lsbfirst << n;)

    //v |= digitalRead(DATA_PIN) << (7 - p);

    v |= digitalState(DATA_PIN) << (7 - p);

    p++;

    if (p == 8) {

      if (buf_num) {

        data_1[index] = v;

      }

      else {

        data_2[index] = v;

      }

      v = 0;

      p = 0;

      index++;

      if (index == DATA_SIZE) {

        sendData = true;

      }

    }

  }

}