SdFat: Arduino/libraries/SdFat/src/SdFatConfig.h File Reference

SdFat

Macros
SdFatConfig.h File Reference

configuration definitions More...

`#include <Arduino.h>`
`#include <stdint.h>`
Include dependency graph for SdFatConfig.h:
This graph shows which files directly or indirectly include this file:

## Macros
#define | CHECK_FLASH_PROGRAMMING 1
#define | DESTRUCTOR_CLOSES_FILE 0
#define | ENABLE_EXTENDED_TRANSFER_CLASS 0
#define | ENABLE_SDIO_CLASS 0
#define | ENABLE_SOFTWARE_SPI_CLASS 0
#define | ENDL_CALLS_FLUSH 0
#define | FAT12_SUPPORT 0
#define | IMPLEMENT_SPI_PORT_SELECTION 0
#define | INCLUDE_SDIOS 1
#define | MAINTAIN_FREE_CLUSTER_COUNT 0
#define | SD_HAS_CUSTOM_SPI 0
#define | USE_FCNTL_H 0
#define | USE_LONG_FILE_NAMES 1
#define | USE_MULTI_BLOCK_IO 1
#define | USE_SD_CRC 0
#define | USE_SEPARATE_FAT_CACHE 0
#define | USE_STANDARD_SPI_LIBRARY 0
#define | WDT_YIELD_TIME_MICROS 0

## Detailed Description

configuration definitions

Copyright (c) 2011-2018 Bill Greiman This file is part of the SdFat library for SD memory cards.

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

## Macro Definition Documentation

## ◆ CHECK_FLASH_PROGRAMMING

#define CHECK_FLASH_PROGRAMMING 1

If CHECK_FLASH_PROGRAMMING is zero, overlap of single sector flash programming and other operations will be allowed for faster write performance.

Some cards will not sleep in low power mode unless CHECK_FLASH_PROGRAMMING is non-zero.

## ◆ DESTRUCTOR_CLOSES_FILE

#define DESTRUCTOR_CLOSES_FILE 0

Set DESTRUCTOR_CLOSES_FILE nonzero to close a file in its destructor.

Causes use of lots of heap in ARM.

## ◆ ENABLE_EXTENDED_TRANSFER_CLASS

#define ENABLE_EXTENDED_TRANSFER_CLASS 0

If the symbol ENABLE_EXTENDED_TRANSFER_CLASS is nonzero, the class SdFatEX will be defined. If the symbol ENABLE_SOFTWARE_SPI_CLASS is also nonzero, the class SdFatSoftSpiEX will be defined.

These classes used extended multi-block SD I/O for better performance. the SPI bus may not be shared with other devices in this mode.

## ◆ ENABLE_SDIO_CLASS

#define ENABLE_SDIO_CLASS 0

Enable SDIO driver if available.

## ◆ ENABLE_SOFTWARE_SPI_CLASS

#define ENABLE_SOFTWARE_SPI_CLASS 0

If the symbol ENABLE_SOFTWARE_SPI_CLASS is nonzero, the class SdFatSoftSpi will be defined. If ENABLE_EXTENDED_TRANSFER_CLASS is also nonzero, the class SdFatSoftSpiEX will be defined.

## ◆ ENDL_CALLS_FLUSH

#define ENDL_CALLS_FLUSH 0

Call flush for endl if ENDL_CALLS_FLUSH is nonzero

The standard for iostreams is to call flush. This is very costly for SdFat. Each call to flush causes 2048 bytes of I/O to the SD.

SdFat has a single 512 byte buffer for SD I/O so it must write the current data block to the SD, read the directory block from the SD, update the directory entry, write the directory block to the SD and read the data block back into the buffer.

The SD flash memory controller is not designed for this many rewrites so performance may be reduced by more than a factor of 100.

If ENDL_CALLS_FLUSH is zero, you must call flush and/or close to force all data to be written to the SD.

## ◆ FAT12_SUPPORT

#define FAT12_SUPPORT 0

Set FAT12_SUPPORT nonzero to enable use if FAT12 volumes. FAT12 has not been well tested and requires additional flash.

## ◆ IMPLEMENT_SPI_PORT_SELECTION

#define IMPLEMENT_SPI_PORT_SELECTION 0

Check if API to select HW SPI port is needed.

## ◆ INCLUDE_SDIOS

#define INCLUDE_SDIOS 1

Set INCLUDE_SDIOS nonzero to include sdios.h in SdFat.h. sdios.h provides C++ style IO Streams.

## ◆ MAINTAIN_FREE_CLUSTER_COUNT

#define MAINTAIN_FREE_CLUSTER_COUNT 0

Set MAINTAIN_FREE_CLUSTER_COUNT nonzero to keep the count of free clusters updated. This will increase the speed of the freeClusterCount() call after the first call. Extra flash will be required.

## ◆ SD_HAS_CUSTOM_SPI

#define SD_HAS_CUSTOM_SPI 0

Determine the default SPI configuration.

## ◆ USE_FCNTL_H

#define USE_FCNTL_H 0

If the symbol USE_FCNTL_H is nonzero, open flags for access modes O_RDONLY, O_WRONLY, O_RDWR and the open modifiers O_APPEND, O_CREAT, O_EXCL, O_SYNC will be defined by including the system file fcntl.h.

## ◆ USE_LONG_FILE_NAMES

#define USE_LONG_FILE_NAMES 1

Set USE_LONG_FILE_NAMES nonzero to use long file names (LFN). Long File Name are limited to a maximum length of 255 characters.

This implementation allows 7-bit characters in the range 0X20 to 0X7E except the following characters are not allowed:

< (less than)

> (greater than)

: (colon) " (double quote) / (forward slash) \ (backslash) | (vertical bar or pipe) ? (question mark)

- (asterisk)

## ◆ USE_MULTI_BLOCK_IO

#define USE_MULTI_BLOCK_IO 1

Set USE_MULTI_BLOCK_IO nonzero to use multi-block SD read/write.

Don't use mult-block read/write on small AVR boards.

## ◆ USE_SD_CRC

#define USE_SD_CRC 0

To enable SD card CRC checking set USE_SD_CRC nonzero.

Set USE_SD_CRC to 1 to use a smaller CRC-CCITT function. This function is slower for AVR but may be fast for ARM and other processors.

Set USE_SD_CRC to 2 to used a larger table driven CRC-CCITT function. This function is faster for AVR but may be slower for ARM and other processors.

## ◆ USE_SEPARATE_FAT_CACHE

#define USE_SEPARATE_FAT_CACHE 0

Set USE_SEPARATE_FAT_CACHE nonzero to use a second 512 byte cache for FAT table entries. This improves performance for large writes that are not a multiple of 512 bytes.

## ◆ USE_STANDARD_SPI_LIBRARY

#define USE_STANDARD_SPI_LIBRARY 0

If the symbol USE_STANDARD_SPI_LIBRARY is zero, an optimized custom SPI driver is used if it exists. If the symbol USE_STANDARD_SPI_LIBRARY is one, the standard Arduino SPI.h library is used with SPI. If the symbol USE_STANDARD_SPI_LIBRARY is two, the SPI port can be selected with the constructors SdFat(SPIClass* spiPort) and SdFatEX(SPIClass* spiPort).

## ◆ WDT_YIELD_TIME_MICROS

#define WDT_YIELD_TIME_MICROS 0

Handle Watchdog Timer for WiFi modules.

Yield will be called before accessing the SPI bus if it has been more than WDT_YIELD_TIME_MICROS microseconds since the last yield call by SdFat.