contiki/core/dev/spi.h

/* -*- C -*- */
/* @(#)$Id: spi.h,v 1.1 2006/06/17 22:41:17 adamdunkels Exp $ */

#ifndef SPI_H
#define SPI_H

extern unsigned char spi_busy;

void spi_init(void);

/******************************************************************************************************
*  TEXAS INSTRUMENTS INC.,                                                                            *
*  MSP430 APPLICATIONS.                                                                               *
*  Copyright Texas Instruments Inc, 2004                                                              *
 *****************************************************************************************************/

/***********************************************************
	FAST SPI: Low level functions
***********************************************************/

#define FASTSPI_TX(x)\
	do {\
		SPI_TXBUF = x;\
		SPI_WAITFOREOTx();\
	} while(0)

#define FASTSPI_RX(x)\
    do {\
        SPI_TXBUF = 0;\
	    SPI_WAITFOREORx();\
		x = SPI_RXBUF;\
    } while(0)

#define FASTSPI_CLEAR_RX(x) do{ SPI_RXBUF; }while(0)

#define FASTSPI_RX_GARBAGE()\
	do {\
    	SPI_TXBUF = 0;\
		SPI_WAITFOREORx();\
		SPI_RXBUF;\
	} while(0)

#define FASTSPI_TX_MANY(p,c)\
	do {\
		for (u8_t spiCnt = 0; spiCnt < (c); spiCnt++) {\
			FASTSPI_TX(((u8_t*)(p))[spiCnt]);\
		}\
	} while(0)


#define FASTSPI_RX_WORD(x)\
	 do {\
	    SPI_TXBUF = 0;\
        SPI_WAITFOREORx();\
		x = SPI_RXBUF << 8;\
	    SPI_TXBUF = 0;\
		SPI_WAITFOREORx();\
		x |= SPI_RXBUF;\
    } while (0)

#define FASTSPI_TX_ADDR(a)\
	 do {\
		  SPI_TXBUF = a;\
		  SPI_WAITFOREOTx();\
	 } while (0)

#define FASTSPI_RX_ADDR(a)\
	 do {\
		  SPI_TXBUF = (a) | 0x40;\
		  SPI_WAITFOREOTx();\
	 } while (0)



/***********************************************************
	FAST SPI: Register access
***********************************************************/
// 	  s = command strobe
// 	  a = register address
// 	  v = register value

#define FASTSPI_STROBE(s) \
    do {\
		  SPI_ENABLE();\
		  FASTSPI_TX_ADDR(s);\
		  SPI_DISABLE();\
    } while (0)

#define FASTSPI_SETREG(a,v)\
	 do {\
		  SPI_ENABLE();\
		  FASTSPI_TX_ADDR(a);\
		  FASTSPI_TX((u8_t) ((v) >> 8));\
		  FASTSPI_TX((u8_t) (v));\
		  SPI_DISABLE();\
	 } while (0)


#define FASTSPI_GETREG(a,v)\
	 do {\
		  SPI_ENABLE();\
		  FASTSPI_RX_ADDR(a);\
		  v= (u8_t)SPI_RXBUF;\
		  FASTSPI_RX_WORD(v);\
		  clock_delay(1);\
		  SPI_DISABLE();\
	 } while (0)

// Updates the SPI status byte

#define FASTSPI_UPD_STATUS(s)\
	 do {\
		  SPI_ENABLE();\
		  SPI_TXBUF = CC2420_SNOP;\
		  SPI_WAITFOREOTx();\
		  s = SPI_RXBUF;\
		  SPI_DISABLE();\
	 } while (0)

/***********************************************************
	FAST SPI: FIFO Access
***********************************************************/
// 	  p = pointer to the byte array to be read/written
// 	  c = the number of bytes to read/write
// 	  b = single data byte

#define FASTSPI_WRITE_FIFO(p,c)\
	do {\
	    SPI_ENABLE();\
		u8_t i;\
		FASTSPI_TX_ADDR(CC2420_TXFIFO);\
		for (i = 0; i < (c); i++) {\
		    FASTSPI_TX(((u8_t*)(p))[i]);\
		}\
		SPI_DISABLE();\
    } while (0)

#define FASTSPI_WRITE_FIFO_NOCE(p,c)\
	do {\
		FASTSPI_TX_ADDR(CC2420_TXFIFO);\
		for (u8_t spiCnt = 0; spiCnt < (c); spiCnt++) {\
		    FASTSPI_TX(((u8_t*)(p))[spiCnt]);\
		}\
    } while (0)

#define FASTSPI_READ_FIFO_BYTE(b)\
	 do {\
		  SPI_ENABLE();\
		  FASTSPI_RX_ADDR(CC2420_RXFIFO);\
		  SPI_RXBUF;\
		  FASTSPI_RX(b);\
  		  clock_delay(1);\
		  SPI_DISABLE();\
	 } while (0)


#define FASTSPI_READ_FIFO_NO_WAIT(p,c)\
	 do {\
		  u8_t spiCnt;\
		  SPI_ENABLE();\
		  FASTSPI_RX_ADDR(CC2420_RXFIFO);\
		  SPI_RXBUF;\
		  for (spiCnt = 0; spiCnt < (c); spiCnt++) {\
				FASTSPI_RX(((u8_t*)(p))[spiCnt]);\
		  }\
		  clock_delay(1);\
		  SPI_DISABLE();\
	 } while (0)



#define FASTSPI_READ_FIFO_GARBAGE(c)\
	 do {\
		  u8_t spiCnt;\
		  SPI_ENABLE();\
		  FASTSPI_RX_ADDR(CC2420_RXFIFO);\
		  SPI_RXBUF;\
		  for (spiCnt = 0; spiCnt < (c); spiCnt++) {\
				FASTSPI_RX_GARBAGE();\
		  }\
  		  clock_delay(1);\
		  SPI_DISABLE();\
	 } while (0)



/***********************************************************
	FAST SPI: CC2420 RAM access (big or little-endian order)
***********************************************************/
//  FAST SPI: CC2420 RAM access (big or little-endian order)
// 	  p = pointer to the variable to be written
// 	  a = the CC2420 RAM address
// 	  c = the number of bytes to write
// 	  n = counter variable which is used in for/while loops (u8_t)
//
//  Example of usage:
// 	  u8_t n;
// 	  u16_t shortAddress = 0xBEEF;
// 	  FASTSPI_WRITE_RAM_LE(&shortAddress, CC2420RAM_SHORTADDR, 2);


#define FASTSPI_WRITE_RAM_LE(p,a,c,n)\
	 do {\
		  SPI_ENABLE();\
		  FASTSPI_TX(0x80 | (a & 0x7F));\
		  FASTSPI_TX((a >> 1) & 0xC0);\
		  for (n = 0; n < (c); n++) {\
				FASTSPI_TX(((u8_t*)(p))[n]);\
		  }\
		  SPI_DISABLE();\
	 } while (0)

#endif /* SPI_H */