ow.h

/*NB_REVISION*/
 
/*NB_COPYRIGHT*/
 
#include <predef.h>
#include <nbrtos.h>
#include <init.h>
#include <stdio.h>
#include <ctype.h>
#include <sim.h>
#include <pins.h>
#include <cfinter.h>
 
#define OW_CR_PST 0x40   // Presence Set bit
#define OW_CR_RPP 0x80   // Reset/Presence-detect pulse
#define OW_IER_ERBF \
    0x10   // Enable receiver buffer full interrupt, and
           // Receive buffer full flag
#define OW_IER_ETSE 0x08   // Enable transmit shift register empty interrupt
#define OW_IER_ETBE 0x04   // Enable transmit buffer empty interrupt
 
#ifndef OW_HPP_
#define OW_HPP_
 
/*
 * OWState
 *     An enum type that defines the possible states of the 1-Wire module.
 */
enum OWState
{
    NOT_INIT = 0,
    OK = 1,
    READ = 2,
    WRITE = 3
};
 
/*
 *   owDriverStruct
 *       This struct contains the state variables used for the 1-Wire driver.
 *
 *   OW_State state - The state of the 1-Wire module.  See the enumerated type
 *       above.
 *
 *   uint8_t* buf - Points to the data buffer.  This is the memory location
 *       from which data will be read or written to the peripheral.
 *
 *   8int8_t remLength - Counter that keeps track of the number of bytes
 *       that still need to be read or written.
 *
 *   OS_SEM* sem - Pointer to the external semaphore for the OW_read and
 *       OW_write functions.
 */
struct owDriverStruct
{
    volatile OWState state;
    volatile uint8_t *buf;
    volatile int remLength;
    OS_SEM *sem;
 
    // Default constructor
    owDriverStruct() : state(NOT_INIT), buf(NULL), remLength(0), sem(NULL) {}
};
 
/*
 * 1-Wire interrupt service routine.
 *     Called by hardware when event occurs on the 1-Wire Module
 */
void OWMasterIsr();
 
/*
 * OWInit()
 *     This function initializes the 1-Wire module registers and sets up the
 *     interrupt service routine
 */
void OWInit();
 
/*
 * OWDetectDevices()
 *     Generates a reset pulse and listens for a response from external
 *     devices.  Returns true if a device is detected, false otherwise
 */
bool OWDetectDevices();
 
/*
 * OWRead(uint8_t* data, int len, OS_SEM *sem)
 *     Reads len bytes from the 1-Wire Bus.  Data points to the buffer
 *     to which the bytes are read. The function  posts to the semaphore
 *     sem when complete (optional).
 */
OWState OWRead(uint8_t *data, int len, OS_SEM *sem = NULL);
 
/*
 * OWWrite(uint8_t* data, int len, OS_SEM *sem)
 *     Writes len bytes to the 1-Wire Bus.  Data points to the buffer from
 *     which bytes are written.  The function posts to the semaphore
 *     sem when complete (optional).
 */
OWState OWWrite(uint8_t *data, int len, OS_SEM *sem = NULL);
 
/*
 * OWDone()
 *     Returns true if the driver is ready to be used/read/write data on the bus
 */
bool OWDone();
 
#endif /* OW_HPP_ */