To provide more background, here is a list of h/w that I have connected to the Mega, with pin numbers:
// BME280 Temp/Humidity/Pressure - I2C 0x76, 3.3v
// BNO055 9DOF IMU - I2C 0x28, 3.3v
// Adafruit Ultimate GPS (TX=10, RX=11, EN=12), Serial1, 5v
// Adafruit GA1A12S202 Analog Light Sensor - A2, 3.3v
// Adafruit SI1145 UV/IR/Visible Light sensor - I2C 0x60, 3.3v, 10K PU
// MAX9814 Microphone - A7, 3.3v
// SDCard Reader SPI - CS:3, Card detect - 18, 5v
// Vibration Sensor - 19, 3.3v, SW-18010P sensor
// Buzzer - 13
// Tri-Color LED (common cathode), G:A3, B:A4, R:A5
The GPS is using Serial1. I am using the EnableInterrupt library for the vibration sensor. I also have this define before the include of the EnableInterrupt library:
This sets up the vibration sensor interrupt:
enableInterrupt(19, vibrationISR, RISING);