Central Heating controller using the real time clock, PHY module for internet, 1-wire interface for temperature sensors, a system log and a configuration file
Dependencies: net 1-wire lpc1768 crypto clock web fram log
/media/uploads/andrewboyson/heating.sch
/media/uploads/andrewboyson/heating.brd
/media/uploads/andrewboyson/eagle.epf
Diff: fram/fram.c
- Revision:
- 0:3c04f4b47041
- Child:
- 76:3ef2a46c8b1e
diff -r 000000000000 -r 3c04f4b47041 fram/fram.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/fram/fram.c Thu Jan 11 17:40:08 2018 +0000 @@ -0,0 +1,143 @@ +#include <string.h> +#include <stdbool.h> + +#include "spi.h" +#include "log.h" +#include "fram.h" + +#define WREN 0x06 // Set Write Enable Latch 0000 0110B +#define WRDI 0x04 // Reset Write Enable Latch 0000 0100B +#define RDSR 0x05 // Read Status Register 0000 0101B +#define WRSR 0x01 // Write Status Register 0000 0001B +#define READ 0x03 // Read Memory Code 0000 0011B +#define WRITE 0x02 // Write Memory Code 0000 0010B +#define RDID 0x9F // Read Device ID 1001 1111B + +#define FRAM_ID 0x047f0302 +#define FRAM_MAGIC 42 //Magic number to show that the FRAM has been intialised + +bool FramEmpty; //Set in FramInit +int FramUsed; //Initialised in FramInit and used by FramAllocate to remember the next available location + +int FramAllocate(int size) //Allocates a number of bytes in FRAM +{ + int start = FramUsed; + int used = FramUsed + size; + if (used > FRAM_SIZE - 1) + { + Log("FramAllocate - No more room in FRAM\r\n"); + return -1; + } + FramUsed = used; + return start; +} +int FramInit() +{ + //Configure SPI + SpiInit(); + + //Check if the FRAM is connected and working properly + SpiChipSelect(0); + SpiTransfer(RDID); + int id = 0; + id = (id << 8) + SpiTransfer(0); + id = (id << 8) + SpiTransfer(0); + id = (id << 8) + SpiTransfer(0); + id = (id << 8) + SpiTransfer(0); + SpiChipSelect(1); + if (id != FRAM_ID) + { + LogF("FramInit - Expected FRAM id %08x but got %08x\r\n", FRAM_ID, id); + return -1; + } + + //Check the first byte to see if the FRAM is initialised and zero if not + SpiChipSelect(0); + SpiTransfer(READ); + SpiTransfer(0); + SpiTransfer(0); + char magic = SpiTransfer(0); + SpiChipSelect(1); + FramEmpty = magic != FRAM_MAGIC; + if (FramEmpty) + { + LogF("FramInit - Byte 0 value %d is not the magic value %d so initialising FRAM to zero\r\n", magic, FRAM_MAGIC); + SpiChipSelect(0); + SpiTransfer(WREN); + SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); + SpiChipSelect(0); + SpiTransfer(WRITE); + SpiTransfer(0); + SpiTransfer(0); + SpiTransfer(FRAM_MAGIC); //Set the magic number in byte 0 + for(int i = 1; i < FRAM_SIZE; i++) SpiTransfer(0); //Zero all other locations + SpiChipSelect(1); + } + FramUsed = 1; //Set the next available location to one past the byte used for the magic number + return 0; +} +void FramWrite(int address, int len, void* pVoid) +{ + if (address + len > FRAM_SIZE - 1 || address < 0) + { + Log("FramWrite - Invalid FRAM address\r\n"); + return; + } + SpiChipSelect(0); + SpiTransfer(WREN); + SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); SpiChipSelect(1); //Deselect must be at least 60ns. One operation at 96MHz is about 10ns + SpiChipSelect(0); + SpiTransfer(WRITE); + SpiTransfer(address >> 8); + SpiTransfer(address & 0xFF); + char* p = (char*)pVoid; + for (int i = 0; i < len; i++) SpiTransfer(*p++); + SpiChipSelect(1); +} +void FramRead(int address, int len, void* pVoid) +{ + if (address + len > FRAM_SIZE - 1 || address < 0) + { + Log("FramRead - Invalid FRAM address\r\n"); + return; + } + SpiChipSelect(0); + SpiTransfer(READ); + SpiTransfer(address >> 8); + SpiTransfer(address & 0xFF); + char* p = (char*)pVoid; + for (int i = 0; i < len; i++) *p++ = SpiTransfer(0); + SpiChipSelect(1); +} + +int FramLoad(int len, void* pValue, void* pDefault) +{ + int address = FramAllocate(len); + if (address >= 0) + { + if (FramEmpty) + { + if (pDefault) + { + int defaultHasContent = 0; + char* pFrom = (char*)pDefault; + char* pTo = (char*)pValue; + for (int i = 0; i < len; i++); + { + if (*pFrom) defaultHasContent = 1; + *pTo++ = *pFrom++; + } + if (defaultHasContent) FramWrite(address, len, pValue); + } + else //pDefault is NULL so zero the setting + { + memset(pValue, 0, len); + } + } + else + { + FramRead(address, len, pValue); + } + } + return address; +}