/*********************************************************************
*               SEGGER MICROCONTROLLER GmbH & Co KG                  *
*       Solutions for real time microcontroller applications         *
**********************************************************************
*                                                                    *
*       (c) 1995 - 2008  SEGGER Microcontroller GmbH & Co KG         *
*                                                                    *
*       www.segger.com     Support: support@segger.com               *
*                                                                    *
**********************************************************************
*                                                                    *
*       embOS * Real time operating system for microcontrollers      *
*                                                                    *
*                                                                    *
*       Please note:                                                 *
*                                                                    *
*       Knowledge of this file may under no circumstances            *
*       be used to write a similar product or a real-time            *
*       operating system for in-house use.                           *
*                                                                    *
*       Thank you for your fairness !                                *
*                                                                    *
**********************************************************************
*                                                                    *
*       embOS version: 3.60a                                         *
*                                                                    *
**********************************************************************

----------------------------------------------------------------------
File    : RTOSInit.c for Texas Instruments MSP430 with IAR compiler
Purpose : Initializes and handles the hardware for embOS as far
          as required by embOS.
          Feel free to modify this file if required for your target
--------  END-OF-HEADER  ---------------------------------------------
*/

#include "RTOS.H"
#include  <msp430.h>

/*********************************************************************
*
*       Configuration
*
**********************************************************************

  Define clock frequency for CPU

  Select UART for embOSView, set baudrate,
  If you do not want (or can not due to hardware limitations) to dedicate
  a UART to embOSView, please define OS_UART to -1

  Define the system stack size that embOS should use. Rowley only

*/

#ifndef   OS_FSYS
  #define OS_FSYS 1000000L
#endif

#ifndef   OS_UART
  #define OS_UART 0
#endif

#ifndef   OS_BAUDSRC_MCLK
  #define OS_BAUDSRC_MCLK 0
#endif

#ifndef   OS_BAUDRATE
  #define OS_BAUDRATE 9600L
#endif

#define EMBOS_TIMER_VECTOR TIMERA0_VECTOR

/****** End of configuration settings *******************************/

/*********************************************************************
*
*       OS_InitHW()
*
*       Initialize the hardware (timer) required for embOS to run.
*       May be modified, if an other timer should be used
*/
void OS_InitHW(void) {
  WDTCTL  = WDTPW + WDTHOLD;    /*  Stop watchdog timer        */

  //
  if (CALBC1_1MHZ ==0xFF || CALDCO_1MHZ == 0xFF)                                     
  {  
    BCSCTL1 = 0x87;                    // Set DCO
    DCOCTL = 0x40;
  }
  else
  {
    BCSCTL1 = CALBC1_1MHZ;             // Set DCO
    DCOCTL = CALDCO_1MHZ;
  }
  
  TACTL   = 0                   /*  Reset Timer_A3, division 1 */
          | (1<<2)              /*  Clear timer                */
          | (2<<8);             /*  Use SMCLK as timer clock    */
  CCR0    = (OS_FSYS/100) - 1;  /*  Set to 10ms                 */
  CCTL0   = 0                   /*  Initilize capture control  */
          | (1<<4);             /*  Enable compare interrupt   */
  TACTL  |= (1<<4);             /*  Start timer in UP-Mode     */
  OS_COM_Init();                /*  Initialize UART            */
}

/*********************************************************************
*
*       Idle loop  (OS_Idle)
*
*       Please note:
*       This is basically the "core" of the idle loop.
*       This core loop can be changed, but:
*       The idle loop does not have a stack of its own, therefore no
*       functionality should be implemented that relies on the stack
*       to be preserved. However, a simple program loop can be programmed
*       (like toggeling an output or incrementing a counter)
*
*       We just enter low power 0 mode here.
*/
void OS_Idle(void) { /* Idle loop: No task is ready to exec         */
  _BIS_SR(0x18);     /* Nothing to do ... enter low power mode 0    */
  for (;;);          /* Alternative endless loop, required          */
                     /* when simulator is used !                    */
}

/*********************************************************************
*
*       Get time [cycles]
*
*       This routine is required for task-info via embOSView or high
*       resolution time maesurement functions.
*       It returns the system time in timer clock cycles.
*/
OS_U32 OS_GetTime_Cycles(void) {
  unsigned int t_cnt = TAR;
  OS_U32 time = OS_Time;
  if (CCTL0 & (1<<0)) {   /* If timer interrupt pending, */
    t_cnt = TAR;          /* correct result              */
    time++;
  }
  return (OS_FSYS/1000)*time  + t_cnt;
}

/*********************************************************************
*
*       OS_ConvertCycles2us
*
*       Convert Cycles into micro seconds.
*
*       If your clock frequency is not a multiple of 1 MHz,
*       you may have to modify this routine in order to get proper
*       diagonstics.
*
*       This routine is required for profiling or high resolution time
*       measurement only. It does not affect operation of the OS.
*/
OS_U32 OS_ConvertCycles2us(OS_U32 Cycles) {
  #if (OS_FSYS >= 1000000)
    return Cycles/(OS_FSYS/1000000);
  #else
    return Cycles * (1000000/OS_FSYS);
  #endif
}

/*********************************************************************
*
*       OS_Tick interrupt Handler
*/
#pragma vector=EMBOS_TIMER_VECTOR
static __interrupt void OS_ISR_Tick(void) {
  OS_EnterInterrupt();
  OS_HandleTick();
  OS_LeaveInterrupt();
}

/*********************************************************************
*
*       Communication for embOSView   (UART 0)
*
**********************************************************************
*/

#if OS_BAUDSRC_MCLK
  #define BAUDDIVIDE ((OS_FSYS+(OS_BAUDRATE/2))/OS_BAUDRATE)
  #define UxBR0  (BAUDDIVIDE & 0xFF)
  #define UxBR1  ((BAUDDIVIDE >> 8) & 0xFF)
  #define UxMCTL 0x00
  #define UxTCTL 0x20            /* Use MCLK for baudrate generator */
#else
  #define UxTCTL 0x10            /* Use ACLK for baudrate generator */
  #if   (OS_BAUDRATE == 9600)
    #define UxBR0  0x03
    #define UxBR1  0x00
    #define UxMCTL 0x4A
  #elif (OS_BAUDRATE == 4800)
    #define UxBR0  0x06
    #define UxBR1  0x00
    #define UxMCTL 0x6F
  #else
    #error Setting of OS_BAUDRATE not supported when using ACLK for baudrate generation
  #endif
#endif

#if (OS_UART == 0)

#define EMBOS_UARTRX_VECTOR USCIAB0RX_VECTOR
#define EMBOS_UARTTX_VECTOR USCIAB0TX_VECTOR

/*********************************************************************
*
*       OS_COM_Init()
*       Initialize UART for embOSView
*/
void OS_COM_Init(void) {	
  P3SEL = 0x30;                             // P3.4,5 = USCI_A0 TXD/RXD
  P3DIR = 0xFF;                             // All P3.x outputs
  P3OUT = 0;                                // All P3.x reset
  
  BCSCTL1 = CALBC1_1MHZ;                    // Set DCO
  DCOCTL = CALDCO_1MHZ;

  UCA0CTL1 |= UCSSEL_2;                     // SMCLK
//  UCA0BR0 = 104;                            // 1MHz 9600
//  UCA0BR1 = 0;                              // 1MHz 9600
  UCA0BR0 = 64;                             // 1MHz 1200
  UCA0BR1 = 3;                              // 1MHz 1200
  UCA0MCTL = UCBRS0;                        // Modulation UCBRSx = 1
  UCA0CTL1 &= ~UCSWRST;                     // **Initialize USCI state machine**
  
  IE2 |= ( UCA0RXIE | UCA0TXIE );           // Enable USCI_A0 RX interrupt
}

/*********************************************************************
*
*       OS_COM_Send1()
*       Never call this function directly from your application
*/
void OS_COM_Send1(OS_U8 c) {
  UCA0TXBUF = c;
}

/*********************************************************************
*
*       OS_ISR_rx()
*       embOS UART rx interrupt handler
*/
#pragma vector=EMBOS_UARTRX_VECTOR
static __interrupt void OS_ISR_rx(void) {
  IE2 &= ~UCA0RXIE;
  OS_EnterNestableInterrupt(); /* We will enable interrupts         */
  OS_OnRx(UCA0RXBUF);            /* Process data                      */
  OS_DI();
  IE2 |= UCA0RXIE;
  OS_LeaveNestableInterrupt();
}

/*********************************************************************
*
*       OS_ISR_tx()
*       embOS UART tx interrupt handler
*/
#pragma vector=EMBOS_UARTTX_VECTOR
static __interrupt void OS_ISR_tx(void) {
  OS_EnterInterrupt();
  IFG2 &= ~UCA0TXIFG;
  OS_OnTx();
  OS_LeaveInterrupt();
}

#elif (OS_UART == -1)          /* No communication routines         */
  void OS_COM_Init(void) {}
  void OS_COM_Send1(OS_U8 c) {
    OS_USEPARA(c);
    OS_COM_ClearTxActive();    /* let OS know that tx is not busy   */
  }

#else  /* unsupported USART selected */
  #error Unsupported USART (OS_UART) selected !!!
#endif /* (OS_UART == 0) */

/*****  EOF  ********************************************************/