Error writing to file/closing file #20
Description
I followed the example provided to write files using a Portenta Machine Control board but I'm having no luck actually writing to files.
As you can see in my code below I've mashed together the directory read example and the file writing example so I could test whether it was a general problem with my USB connection/drive but I can read the files in the directory properly, but cannot seem to write.
You'll see also below in the console print out there is no issue with the writing inside the for loop to write the numbers, only when it's time to close.
When I check the USB in my computer there is no data written to that file (it's a file I've created previously. If I delete it no new file is created).
My code:
/*
Portenta - FileWrite
The sketch shows how to mount an usb storage device and how to
write a file, eventually overwriting the original content.
The circuit:
- Portenta H7
This example code is in the public domain.
*/
#include <Arduino_MachineControl.h>
#include <Arduino_USBHostMbed5.h> //https://github.com/arduino-libraries/Arduino_USBHostMbed5
#include <DigitalOut.h>
//#include <FATFileSystem.h>
using namespace machinecontrol;
// Redirect log output from MbedOS and low-level libraries to Serial
REDIRECT_STDOUT_TO(Serial);
USBHostMSD msd;
mbed::FATFileSystem usb("usb");
//to enable thte usb otg power:
mbed::DigitalOut otg(PB_14, 0);
int err = 0;
void setup() {
//usb_controller.powerEnable();
Serial.begin(115200);
//while (!Serial);
delay(2000);
Serial.print("Trying MSD connect");
while (!msd.connect()) {
delay(1000);
Serial.print(".");
}
Serial.println("success");
Serial.println("Mounting USB device...");
err = usb.mount(&msd);
if (err) {
Serial.print("Error mounting USB device ");
Serial.println(err);
while (1)
;
}
Serial.print("read done ");
dirRead();
fileWrite();
}
void loop() {
delay(1000);
// handle disconnection and reconnection
if (!msd.connected()) {
msd.connect();
}
}
void fileWrite() {
mbed::fs_file_t file;
struct dirent* ent;
int dirIndex = 0;
int res = 0;
Serial.println("Open /usb/numbers.txt");
FILE* f = fopen("/usb/numbers.txt", "w+"); //w+ = create a new file for update. See: https://os.mbed.com/users/berntzen/notebook/writing-files/
printf("%s\n", (!f ? "Fail :(" : "OK"));
for (int i = 1; i <= 10; i++) {
Serial.print("Writing numbers (");
Serial.print(i);
Serial.println("/10)");
fflush(stdout);
err = fprintf(f, "%d\n", i);
if (err < 0) {
Serial.println("Fail :(");
error("error: %s (%d)\n", strerror(errno), -errno);
}
//do we need to go a bit more slowly?
delay(100);
}
delay(1000);
Serial.println("closing file..");
err = fclose(f);
if (err < 0) {
Serial.print("fclose error:");
Serial.print(strerror(errno));
Serial.print(" (");
Serial.print(-errno);
Serial.print(")");
} else {
Serial.println("File closed");
}
}
void dirRead() {
char buf[256];
// Display the root directory
Serial.print("Opening the root directory... ");
DIR* d = opendir("/usb/");
Serial.println(!d ? "Fail :(" : "Done");
if (!d) {
snprintf(buf, sizeof(buf), "error: %s (%d)\r\n", strerror(errno), -errno);
Serial.print(buf);
}
Serial.println("done.");
Serial.println("Root directory:");
unsigned int count{ 0 };
while (true) {
struct dirent* e = readdir(d);
if (!e) {
break;
}
count++;
snprintf(buf, sizeof(buf), " %s\r\n", e->d_name);
Serial.print(buf);
}
Serial.print(count);
Serial.println(" files found!");
snprintf(buf, sizeof(buf), "Closing the root directory... ");
Serial.print(buf);
fflush(stdout);
err = closedir(d);
snprintf(buf, sizeof(buf), "%s\r\n", (err < 0 ? "Fail :(" : "OK"));
Serial.print(buf);
if (err < 0) {
snprintf(buf, sizeof(buf), "error: %s (%d)\r\n", strerror(errno), -errno);
Serial.print(buf); delay(1000);
// handle disconnection and reconnection
if (!msd.connected()) {
msd.connect();
}
}
}
And the console print out:
Trying MSD connect.success
Mounting USB device...
read done Opening the root directory... Done
done.
Root directory:
numbers.txt
1 files found!
Closing the root directory... OK
Open /usb/numbers.txt
OK
Writing numbers (1/10)
Writing numbers (2/10)
Writing numbers (3/10)
Writing numbers (4/10)
Writing numbers (5/10)
Writing numbers (6/10)
Writing numbers (7/10)
Writing numbers (8/10)
Writing numbers (9/10)
Writing numbers (10/10)
closing file..
fclose error:I/O error (-5)