#ifndef	MCP2515_CFG_H
#define	MCP2515_CFG_H

// SPI port definition
#define	P_MOSI			B,2
#define	P_MISO			B,3
#define	P_SCK			B,1

#define	MCP2515_CS		B,0
#define	MCP2515_INT		E,5

// bit timing definition
// this are the register values written! Observe the formulas
// CAN baud rate 125kbit/s
// Prescaler 10MHz/8 = 1,25MHz
// T_BIT = 10 * TQ

#define CFG_SJW      0      // 1, not part of fixed bit timing
#define CFG_BRP      3      // TQ = (2 * (BRP + 1)) / F_CPU     

                            //                                  TQ
                            // SyncSEG constant                  1 
#define CFG_PRSEG    0      // t_PropSeg = TQ * (PRSEG  + 1)     1 
#define CFG_PHSEG1   3      // t_PS1     = TQ * (PHSEG1 + 1)     4
#define CFG_PHSEG2   3      // t_PS2     = TQ * (PHSEG2 + 1)     4
                            //                                 ---
                            //                           total  10

// ----------------------------------------------------------------------------

#define	RESET(x)		_XRS(x)
#define	SET(x)			_XS(x)
#define	TOGGLE(x)		_XT(x)
#define	SET_OUTPUT(x)	_XSO(x)
#define	SET_INPUT(x)	_XSI(x)
#define	IS_SET(x)		_XR(x)

#define	PORT(x)			_port2(x)
#define	DDR(x)			_ddr2(x)
#define	PIN(x)			_pin2(x)

#define	_XRS(x,y)	PORT(x) &= ~(1<<y)
#define	_XS(x,y)	PORT(x) |= (1<<y)
#define	_XT(x,y)	PORT(x) ^= (1<<y)

#define	_XSO(x,y)	DDR(x) |= (1<<y)
#define	_XSI(x,y)	DDR(x) &= ~(1<<y)

#define	_XR(x,y)	((PIN(x) & (1<<y)) != 0)

#define	_port2(x)	PORT ## x
#define	_ddr2(x)	DDR ## x
#define	_pin2(x)	PIN ## x

#endif	// MCP2515_CFG_H