(help)arduino yun,Write micro SD

Hello everyone
Has been updated Linino
As long as there Bridge.begin(); yun No response

Thank you

I guess FileIO.h or Bridge.begin() error
I joined LED But No action

#include <FileIO.h>
void setup() {
pinMode(13, OUTPUT);
Bridge.begin();
Serial.begin(19200);
FileSystem.begin();
while(!Serial);
}
void loop () {
digitalWrite(13, HIGH);
delay(500);
digitalWrite(13, LOW);
delay(500);
const char filenamepath = “/mnt/sda1/data.txt”;