Pierre Emmibed
Library for the SST25VF016B serial flash from Microchip (16Mbit Serial Flash).
SST25VF.h@0:1633dfa4b768, 2012-01-15 (annotated)
- Committer:
- emmibed
- Date:
- Sun Jan 15 13:51:16 2012 +0000
- Revision:
- 0:1633dfa4b768
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| emmibed | 0:1633dfa4b768 | 1 | /** SST25VF - drive the Microchip SST25VF Serial Flash using SPI |
| emmibed | 0:1633dfa4b768 | 2 | * |
| emmibed | 0:1633dfa4b768 | 3 | * Assumes spi mode is default (8,0). |
| emmibed | 0:1633dfa4b768 | 4 | * |
| emmibed | 0:1633dfa4b768 | 5 | * You can clock the SST25VF at up to >20MHz, so it supports the mbed's maximum SPI frequency of 12MHz. |
| emmibed | 0:1633dfa4b768 | 6 | */ |
| emmibed | 0:1633dfa4b768 | 7 | |
| emmibed | 0:1633dfa4b768 | 8 | #include "mbed.h" |
| emmibed | 0:1633dfa4b768 | 9 | |
| emmibed | 0:1633dfa4b768 | 10 | /* ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| emmibed | 0:1633dfa4b768 | 11 | * ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| emmibed | 0:1633dfa4b768 | 12 | * Caution: Do not write to adresses where data != 0xFF |
| emmibed | 0:1633dfa4b768 | 13 | * Data in selected adress range MUST be 0xFF (See datasheet) |
| emmibed | 0:1633dfa4b768 | 14 | * ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| emmibed | 0:1633dfa4b768 | 15 | * ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| emmibed | 0:1633dfa4b768 | 16 | */ |
| emmibed | 0:1633dfa4b768 | 17 | |
| emmibed | 0:1633dfa4b768 | 18 | #ifndef SST25VF_H |
| emmibed | 0:1633dfa4b768 | 19 | #define SST25VF_H |
| emmibed | 0:1633dfa4b768 | 20 | |
| emmibed | 0:1633dfa4b768 | 21 | #define SPI_FREQ 12000000 // 12Mhz is mbed max (one eight of periph. clock) |
| emmibed | 0:1633dfa4b768 | 22 | |
| emmibed | 0:1633dfa4b768 | 23 | #define waitShort() wait_us(10) |
| emmibed | 0:1633dfa4b768 | 24 | #define waitErase() wait_ms(50) |
| emmibed | 0:1633dfa4b768 | 25 | |
| emmibed | 0:1633dfa4b768 | 26 | // command codes for SST25VF |
| emmibed | 0:1633dfa4b768 | 27 | #define WRITE_STATUS 0x01 // called WRSR in datasheet |
| emmibed | 0:1633dfa4b768 | 28 | #define WRITE 0x02 // Byte-Program |
| emmibed | 0:1633dfa4b768 | 29 | #define READ 0x03 |
| emmibed | 0:1633dfa4b768 | 30 | #define WRDI 0x04 |
| emmibed | 0:1633dfa4b768 | 31 | #define READ_STATUS 0x05 // called RDSR |
| emmibed | 0:1633dfa4b768 | 32 | #define WREN 0x06 |
| emmibed | 0:1633dfa4b768 | 33 | //#define HSREAD 0x0B // High-Speed-Read |
| emmibed | 0:1633dfa4b768 | 34 | #define EWSR 0x50 // Enable-Write-Status-Register |
| emmibed | 0:1633dfa4b768 | 35 | #define CHIP_ERASE 0x60 |
| emmibed | 0:1633dfa4b768 | 36 | #define AAIWRITE 0xAD // word based write |
| emmibed | 0:1633dfa4b768 | 37 | |
| emmibed | 0:1633dfa4b768 | 38 | class SST25VF { |
| emmibed | 0:1633dfa4b768 | 39 | public: |
| emmibed | 0:1633dfa4b768 | 40 | /** Create an interface |
| emmibed | 0:1633dfa4b768 | 41 | * |
| emmibed | 0:1633dfa4b768 | 42 | * |
| emmibed | 0:1633dfa4b768 | 43 | * @param spi An SPI object |
| emmibed | 0:1633dfa4b768 | 44 | * @param ncs Not chip select pin - any free Digital pin will do |
| emmibed | 0:1633dfa4b768 | 45 | */ |
| emmibed | 0:1633dfa4b768 | 46 | SST25VF(SPI& spi, PinName ncs); |
| emmibed | 0:1633dfa4b768 | 47 | /** read a byte from SRAM |
| emmibed | 0:1633dfa4b768 | 48 | * @param address The address to read from |
| emmibed | 0:1633dfa4b768 | 49 | * @return the character at that address |
| emmibed | 0:1633dfa4b768 | 50 | */ |
| emmibed | 0:1633dfa4b768 | 51 | char read(long int address); |
| emmibed | 0:1633dfa4b768 | 52 | |
| emmibed | 0:1633dfa4b768 | 53 | /** read multiple bytes from SRAM into a buffer |
| emmibed | 0:1633dfa4b768 | 54 | * @param address The SRAM address to read from |
| emmibed | 0:1633dfa4b768 | 55 | * @param buffer The buffer to read into (must be big enough!) |
| emmibed | 0:1633dfa4b768 | 56 | * @param count The number of bytes to read |
| emmibed | 0:1633dfa4b768 | 57 | */ |
| emmibed | 0:1633dfa4b768 | 58 | void read(long int address, char * buffer, int count); |
| emmibed | 0:1633dfa4b768 | 59 | /** write a byte to SRAM |
| emmibed | 0:1633dfa4b768 | 60 | * @param address The address SRAM to write to |
| emmibed | 0:1633dfa4b768 | 61 | * @param byte The byte to write there |
| emmibed | 0:1633dfa4b768 | 62 | */ |
| emmibed | 0:1633dfa4b768 | 63 | void write(long int address, char byte); |
| emmibed | 0:1633dfa4b768 | 64 | /** write multiple bytes to SRAM from a buffer |
| emmibed | 0:1633dfa4b768 | 65 | * @param address The SRAM address write to |
| emmibed | 0:1633dfa4b768 | 66 | * @param buffer The buffer to write from |
| emmibed | 0:1633dfa4b768 | 67 | * @param count The number of bytes to write |
| emmibed | 0:1633dfa4b768 | 68 | */ |
| emmibed | 0:1633dfa4b768 | 69 | void write(long int address, char * buffer, int count); |
| emmibed | 0:1633dfa4b768 | 70 | |
| emmibed | 0:1633dfa4b768 | 71 | |
| emmibed | 0:1633dfa4b768 | 72 | void chipErase(); |
| emmibed | 0:1633dfa4b768 | 73 | char readStatus(); |
| emmibed | 0:1633dfa4b768 | 74 | |
| emmibed | 0:1633dfa4b768 | 75 | private: |
| emmibed | 0:1633dfa4b768 | 76 | SPI& _spi; |
| emmibed | 0:1633dfa4b768 | 77 | DigitalOut _ncs; |
| emmibed | 0:1633dfa4b768 | 78 | |
| emmibed | 0:1633dfa4b768 | 79 | void writeStatus(char status); |
| emmibed | 0:1633dfa4b768 | 80 | void prepareCommand(char command, long int address); |
| emmibed | 0:1633dfa4b768 | 81 | void select(); |
| emmibed | 0:1633dfa4b768 | 82 | void deselect(); |
| emmibed | 0:1633dfa4b768 | 83 | void wren(); |
| emmibed | 0:1633dfa4b768 | 84 | void unlock(); |
| emmibed | 0:1633dfa4b768 | 85 | void wrdi(); |
| emmibed | 0:1633dfa4b768 | 86 | }; |
| emmibed | 0:1633dfa4b768 | 87 | |
| emmibed | 0:1633dfa4b768 | 88 | #endif |