X-Git-Url: http://git.rot13.org/?p=goodfet;a=blobdiff_plain;f=firmware%2Fapps%2Fspi%2Fspi.c;h=dd92ba2096fc41f76cac5dbf09b7107cd70dd2a6;hp=0a15799a084762d27780e34deb3779246672f0e6;hb=97143fece53250662a3ffd22f141619a4902eda7;hpb=4cf3fdb6a6d9a8844481d661e4d4c957c6a2ec87 diff --git a/firmware/apps/spi/spi.c b/firmware/apps/spi/spi.c index 0a15799..dd92ba2 100644 --- a/firmware/apps/spi/spi.c +++ b/firmware/apps/spi/spi.c @@ -1,5 +1,7 @@ -//GoodFET SPI Application -//Handles basic I/O +/*! \file spi.c + \author Travis Goodspeed + \brief SPI Master +*/ //Higher level left to client application. @@ -10,36 +12,31 @@ #include #include - -//Pins and I/O -#define SS BIT0 -#define MOSI BIT1 -#define MISO BIT2 -#define SCK BIT3 +#include "spi.h" //This could be more accurate. //Does it ever need to be? #define SPISPEED 0 -#define SPIDELAY(x) delay(x) - -#define SETMOSI P5OUT|=MOSI -#define CLRMOSI P5OUT&=~MOSI -#define SETCLK P5OUT|=SCK -#define CLRCLK P5OUT&=~SCK -#define READMISO (P5IN&MISO?1:0) - +#define SPIDELAY(x) +//delay(x) //! Set up the pins for SPI mode. void spisetup(){ - P5OUT|=SS; - P5DIR|=MOSI+SCK+SS; + SETSS; + P5DIR|=MOSI+SCK; //BIT0 might be SS P5DIR&=~MISO; + DIRSS; + + //Begin a new transaction. + CLRSS; + SETSS; } -//! Read and write an SPI bit. + +//! Read and write an SPI byte. unsigned char spitrans8(unsigned char byte){ - unsigned int bit; + register unsigned int bit; //This function came from the SPI Wikipedia article. //Minor alterations. @@ -51,13 +48,8 @@ unsigned char spitrans8(unsigned char byte){ CLRMOSI; byte <<= 1; - /* half a clock cycle before leading/rising edge */ - SPIDELAY(SPISPEED/2); SETCLK; - - /* half a clock cycle before trailing/falling edge */ - SPIDELAY(SPISPEED/2); - + /* read MISO on trailing edge */ byte |= READMISO; CLRCLK; @@ -66,73 +58,233 @@ unsigned char spitrans8(unsigned char byte){ return byte; } + //! Enable SPI writing void spiflash_wrten(){ - P5OUT&=~SS; //Drop !SS to begin transaction. - spitrans8(0x04);//Write Disable - P5OUT|=SS; //Raise !SS to end transaction. - P5OUT&=~SS; //Drop !SS to begin transaction. - spitrans8(0x06);//Write Enable - P5OUT|=SS; //Raise !SS to end transaction. + SETSS; + /* + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x04);//Write Disable + SETSS; //Raise !SS to end transaction. + */ + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x06);//Write Enable + SETSS; //Raise !SS to end transaction. +} + + +//! Grab the SPI flash status byte. +unsigned char spiflash_status(){ + unsigned char c; + SETSS; //Raise !SS to end transaction. + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x05);//GET STATUS + c=spitrans8(0xFF); + SETSS; //Raise !SS to end transaction. + return c; +} + + +//! Grab the SPI flash status byte. +void spiflash_setstatus(unsigned char c){ + SETSS; + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x01);//SET STATUS + spitrans8(c); + SETSS; //Raise !SS to end transaction. + //return c; +} + + +//! Read a block to a buffer. +void spiflash_peekblock(unsigned long adr, + unsigned char *buf, + unsigned int len){ + unsigned char i; + + SETSS; + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x03);//Flash Read Command + + //Send address + spitrans8((adr&0xFF0000)>>16); + spitrans8((adr&0xFF00)>>8); + spitrans8(adr&0xFF); + + for(i=0;i>16); + spitrans8((adr&0xFF00)>>8); + spitrans8(adr&0xFF); + + for(i=0;i0x100?0x100:len-off); + //write the block + spiflash_pokeblock(adr+off, + buf+off, + blen); + //add offset + off+=blen; + } } + + +//! Peek some blocks. +void spiflash_peek(unsigned char app, + unsigned char verb, + unsigned long len){ + unsigned int i; + CLRSS; //Drop !SS to begin transaction. + spitrans8(0x03);//Flash Read Command + len=3;//write 3 byte pointer + for(i=0;i>16); + spitrans8((adr&0xFF00)>>8); + spitrans8(adr&0xFF); + + SETSS; + while(spiflash_status()&0x01);//while busy + //debugstr("Erased."); +} + + //! Handles a monitor command. void spihandle(unsigned char app, unsigned char verb, - unsigned char len){ - unsigned char i; + unsigned long len){ + unsigned long i; + + //Raise !SS to end transaction, just in case we forgot. + SETSS; + spisetup(); + switch(verb){ //PEEK and POKE might come later. case READ: case WRITE: - P5OUT&=~SS; //Drop !SS to begin transaction. + CLRSS; //Drop !SS to begin transaction. for(i=0;i