1.7KB
SerialFlash
Use SPI Flash memory with a filesystem-like interface.
Accessing Files
Open A File
SerialFlashFile file;
file = SerialFlash.open("filename.bin");
if (file) { // true if the file exists
Read Data
char buffer[256];
file.read(buffer, 256);
File Size & Positon
file.size();
file.position()
file.seek();
Write Data
file.write(buffer, 256);
Several limitations apply to writing. Only previously unwritten portions of the file may be written. Files sizes can never change. Writes may only be done within the file’s original size.
file.erase(); // not yet implemented
Only files created for erasing can be erased. The entire file is erased to all 255 (0xFF) bytes.
Managing Files
Create New Files
SerialFlash.create(filename, size);
SerialFlash.createErasable(filename, size);
New files must be created using these funtions. Each returns true if the file is successfully created, or false if not enough space is available.
Once created, files can never be renamed or deleted. The file’s size can never change. Writing additional data can NOT grow the size of file.
Files created for erasing automatically increase in size to the nearest number of erasable blocks, resulting in a file that may be 4K to 128K larger than requested.
Directory Listing
SerialFlash.opendir();
SerialFlash.readdir(buffer, buflen, filelen);
A list of files stored in the Flash can be accessed with readdir(), which returns true for each file, or false to indicate no more files.
Full Erase
SerialFlash.erase();
while (SerialFlash.ready() == false) {
// wait, 30 seconds to 2 minutes for most chips
}