When I load the following sketch it loads but the ‘Thing Plus’ is not found after it reboots. No com port or anything. Can someone tell me what I am doing wrong? I have reproduced the problem on several boards with and without the sensor attached.
/***************************************************************************
  This is a library for the BMP280 humidity, temperature & pressure sensor
  Designed specifically to work with the Adafruit BMEP280 Breakout
  ----> http://www.adafruit.com/products/2651
  These sensors use I2C or SPI to communicate, 2 or 4 pins are required
  to interface.
  Adafruit invests time and resources providing this open source code,
  please support Adafruit andopen-source hardware by purchasing products
  from Adafruit!
  Written by Limor Fried & Kevin Townsend for Adafruit Industries.
  BSD license, all text above must be included in any redistribution
 ***************************************************************************/
#include <Wire.h>
#include <SPI.h>
#include <Adafruit_BMP280.h>
#define BMP_CS   (10)
//Adafruit_BMP280 bmp; // I2C
Adafruit_BMP280 bmp(BMP_CS); // hardware SPI
//Adafruit_BMP280 bmp(BMP_CS, BMP_MOSI, BMP_MISO,  BMP_SCK);
void setup() {
  Serial.begin(9600);
  Serial.println(F("BMP280 test"));
  if (!bmp.begin()) {
    Serial.println(F("Could not find a valid BMP280 sensor, check wiring!"));
    while (1);
  }
  /* Default settings from datasheet. */
  bmp.setSampling(Adafruit_BMP280::MODE_NORMAL,     /* Operating Mode. */
                  Adafruit_BMP280::SAMPLING_X2,     /* Temp. oversampling */
                  Adafruit_BMP280::SAMPLING_X16,    /* Pressure oversampling */
                  Adafruit_BMP280::FILTER_X16,      /* Filtering. */
                  Adafruit_BMP280::STANDBY_MS_500); /* Standby time. */
}
void loop() {
    Serial.print(F("Temperature = "));
    Serial.print(bmp.readTemperature());
    Serial.println(" *C");
    Serial.print(F("Pressure = "));
    Serial.print(bmp.readPressure());
    Serial.println(" Pa");
    Serial.print(F("Approx altitude = "));
    Serial.print(bmp.readAltitude(1013.25)); /* Adjusted to local forecast! */
    Serial.println(" m");
    Serial.println();
    delay(2000);
}
Thanks.