#include <SPI.h>
#include <SD.h>

const int chipSelect = PB1;
File logFile;

void setup() {
  Serial.begin(9600);
  if (!SD.begin(chipSelect)) {
    Serial.println("SD card initialization failed!");
    return;
  }
  logFile = SD.open("datalog.txt", FILE_WRITE);
  if (!logFile) {
    Serial.println("Failed to open file for writing!");
    return;
  }
  pinMode(PA0, INPUT);
}

void loop() {
  int sensorValue = analogRead(PA0);
  logFile.println(sensorValue);
  logFile.flush();
  Serial.println(sensorValue);
  delay(1000);
}