x
FRAMSPI.h@0:0411eff88bac, 2018-07-23 (annotated)
- Committer:
- JackB
- Date:
- Mon Jul 23 12:23:33 2018 +0000
- Revision:
- 0:0411eff88bac
FRAM
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
JackB | 0:0411eff88bac | 1 | /* FRAM_SPI - Ramtron FRAM FM24VXX series driver |
JackB | 0:0411eff88bac | 2 | * Copyright (c) 2012 Oleg Evsegneev |
JackB | 0:0411eff88bac | 3 | * Released under the MIT License: http://mbed.org/license/mit |
JackB | 0:0411eff88bac | 4 | * |
JackB | 0:0411eff88bac | 5 | * Datasheet http://www.ramtron.com/files/datasheets/FM25V02_ds.pdf |
JackB | 0:0411eff88bac | 6 | */ |
JackB | 0:0411eff88bac | 7 | |
JackB | 0:0411eff88bac | 8 | #ifndef FRAMSPI_ |
JackB | 0:0411eff88bac | 9 | #define FRAMSPI_ |
JackB | 0:0411eff88bac | 10 | |
JackB | 0:0411eff88bac | 11 | #include "mbed.h" |
JackB | 0:0411eff88bac | 12 | |
JackB | 0:0411eff88bac | 13 | // commands |
JackB | 0:0411eff88bac | 14 | #define READ 0x03 |
JackB | 0:0411eff88bac | 15 | #define WRITE 0x02 |
JackB | 0:0411eff88bac | 16 | #define READ_STATUS 0x05 // RDSR |
JackB | 0:0411eff88bac | 17 | #define WRITE_ENABLED 0x06 // WREN |
JackB | 0:0411eff88bac | 18 | #define WRITE_STATUS 0x01 // WRSR |
JackB | 0:0411eff88bac | 19 | #define READ_ID 0x9F // RDID |
JackB | 0:0411eff88bac | 20 | #define READ_SN 0xC3 // RSN |
JackB | 0:0411eff88bac | 21 | |
JackB | 0:0411eff88bac | 22 | /** An interface for the Ramtron FM25VXX FRAM over SPI |
JackB | 0:0411eff88bac | 23 | * |
JackB | 0:0411eff88bac | 24 | * |
JackB | 0:0411eff88bac | 25 | * |
JackB | 0:0411eff88bac | 26 | * @code |
JackB | 0:0411eff88bac | 27 | * #include "mbed.h" |
JackB | 0:0411eff88bac | 28 | * #include "FRAMSPI.h" |
JackB | 0:0411eff88bac | 29 | * |
JackB | 0:0411eff88bac | 30 | * SPI spi(p5,p6,p7); |
JackB | 0:0411eff88bac | 31 | * FRAMSPI fram(spi,p8); |
JackB | 0:0411eff88bac | 32 | * Serial pc(USBTX, USBRX); |
JackB | 0:0411eff88bac | 33 | * |
JackB | 0:0411eff88bac | 34 | * int main() { |
JackB | 0:0411eff88bac | 35 | * char wdata[] = "Hello world!"; |
JackB | 0:0411eff88bac | 36 | * char rdata[14]; |
JackB | 0:0411eff88bac | 37 | * |
JackB | 0:0411eff88bac | 38 | * fram.write(0, wdata, 13); // 12 symbols + zero terminator |
JackB | 0:0411eff88bac | 39 | * fram.read(0, rdata, 13); |
JackB | 0:0411eff88bac | 40 | * |
JackB | 0:0411eff88bac | 41 | * pc.printf("data: %s", rdata); |
JackB | 0:0411eff88bac | 42 | * } |
JackB | 0:0411eff88bac | 43 | * @endcode |
JackB | 0:0411eff88bac | 44 | * connections: |
JackB | 0:0411eff88bac | 45 | * chip pin 1 to any GPIO. Chip select (!S) |
JackB | 0:0411eff88bac | 46 | * chip pin 2 SO to MISO. Write (!W) |
JackB | 0:0411eff88bac | 47 | * chip pin 3 to Vout or N/C |
JackB | 0:0411eff88bac | 48 | * chip pin 4 to Gnd |
JackB | 0:0411eff88bac | 49 | * chip pin 5 SI to MOSI |
JackB | 0:0411eff88bac | 50 | * chip pin 6 SCK to sck |
JackB | 0:0411eff88bac | 51 | * chip pin 7 to Vout. !Hold |
JackB | 0:0411eff88bac | 52 | * chip pin 8 to Vout |
JackB | 0:0411eff88bac | 53 | */ |
JackB | 0:0411eff88bac | 54 | |
JackB | 0:0411eff88bac | 55 | class FRAMSPI { |
JackB | 0:0411eff88bac | 56 | |
JackB | 0:0411eff88bac | 57 | public: |
JackB | 0:0411eff88bac | 58 | /** Create an interface |
JackB | 0:0411eff88bac | 59 | * |
JackB | 0:0411eff88bac | 60 | * @param spi An SPI object |
JackB | 0:0411eff88bac | 61 | * @param ncs Chip select pin |
JackB | 0:0411eff88bac | 62 | */ |
JackB | 0:0411eff88bac | 63 | FRAMSPI(SPI& spi, PinName ncs); |
JackB | 0:0411eff88bac | 64 | |
JackB | 0:0411eff88bac | 65 | /** read chip 8 byte device ID |
JackB | 0:0411eff88bac | 66 | */ |
JackB | 0:0411eff88bac | 67 | void readID(char *buff); |
JackB | 0:0411eff88bac | 68 | |
JackB | 0:0411eff88bac | 69 | /** read chip 2 byte serial number |
JackB | 0:0411eff88bac | 70 | */ |
JackB | 0:0411eff88bac | 71 | void readSN(char *buff); |
JackB | 0:0411eff88bac | 72 | |
JackB | 0:0411eff88bac | 73 | /** read a byte from FRAM |
JackB | 0:0411eff88bac | 74 | * @param addr The address to read from |
JackB | 0:0411eff88bac | 75 | * @return the byte at that address |
JackB | 0:0411eff88bac | 76 | */ |
JackB | 0:0411eff88bac | 77 | char read(int addr); |
JackB | 0:0411eff88bac | 78 | |
JackB | 0:0411eff88bac | 79 | /** read multiple bytes from FRAM into a buffer |
JackB | 0:0411eff88bac | 80 | * @param addr The FRAM address to read from |
JackB | 0:0411eff88bac | 81 | * @param buff The buffer to read into (must be big enough!) |
JackB | 0:0411eff88bac | 82 | * @param cnt The number of bytes to read |
JackB | 0:0411eff88bac | 83 | */ |
JackB | 0:0411eff88bac | 84 | void read(int addr, char *buff, int cnt); |
JackB | 0:0411eff88bac | 85 | |
JackB | 0:0411eff88bac | 86 | /** write a byte to FRAM |
JackB | 0:0411eff88bac | 87 | * @param addr The address SFRAM to write to |
JackB | 0:0411eff88bac | 88 | * @param data The byte to write there |
JackB | 0:0411eff88bac | 89 | */ |
JackB | 0:0411eff88bac | 90 | void write(int addr, char data); |
JackB | 0:0411eff88bac | 91 | |
JackB | 0:0411eff88bac | 92 | /** write multiple bytes to FRAM from a buffer |
JackB | 0:0411eff88bac | 93 | * @param addr The FRAM address write to |
JackB | 0:0411eff88bac | 94 | * @param buff The buffer to write from |
JackB | 0:0411eff88bac | 95 | * @param cnt The number of bytes to write |
JackB | 0:0411eff88bac | 96 | */ |
JackB | 0:0411eff88bac | 97 | void write(int addr, char *buff, int cnt); |
JackB | 0:0411eff88bac | 98 | |
JackB | 0:0411eff88bac | 99 | private: |
JackB | 0:0411eff88bac | 100 | SPI& _spi; |
JackB | 0:0411eff88bac | 101 | DigitalOut _ncs; |
JackB | 0:0411eff88bac | 102 | void prepareCommand(char cmd, int addr); |
JackB | 0:0411eff88bac | 103 | void select(); |
JackB | 0:0411eff88bac | 104 | void deselect(); |
JackB | 0:0411eff88bac | 105 | }; |
JackB | 0:0411eff88bac | 106 | |
JackB | 0:0411eff88bac | 107 | #endif |