timer_a.c

瑞萨单片机LCD控制

                            // +--------- timer A0 event/trigger select bits
                            //            00:  input on TA0in (must be input)
                            //            01:  overflow of timer B2
                            //            10:  overflow of timer A4
                            //            11:  overflow of timer A1

    // Clock prescaler reset flag
    // This function is only effective if fc32 is selected
    if ((TA0MR & 0xC0)==0xC0)
    {
        CPSRF = 0x80;       // 1--- ----                                   
                            // +---------- 1: clock prescaler is reset 
    }
}

/**************************************************************************/
/*                                                                        */
/*       Timer A0 - Initialization for pwm mode                           */
/*       The timer outputs pulses of a given width                        */
/*       routine may be customized to the user's needs                    */
/*                                                                        */
/*       Name         :      timer_a0_init_pwm_mode                       */
/*       Date/Author  :      08.04.1997/ST                                */
/*       Parameter    :                                                   */
/*       Return       :                                                   */
/*                                                                        */
/**************************************************************************/
void near timer_a0_init_pwm_mode (void)
{       
    TA0MR    = 0x01;        // XXXX X111 
                            // |||| |||+- must always be 1 in pwm mode
                            // |||| ||+-- must always be 1 in pwm mode
                            // |||| |+--- must always be 1 in pwm mode
                            // |||| +---- 0: ext. trigger falling edge of
                            // ||||          TA0in input signal
                            // ||||       1: ext. trigger rising edge of
                            // ||||          TA0in input signal
                            // ||||       TA0in must be configured as input
                            // ||||       TA0in must be selected by 
                            // ||||       event/trigger select bits
                            // |||+------ 0: trigger is count start flag (TABSR)
                            // |||        1: trigger is selected by event/trigger
                            // |||           select bits
                            // ||+------- 0: 16-bit pwm
                            // ||         1:  8-bit pwm
                            // |+-------- count source select bits:
                            // +--------- count source select bits:
                            //            00:  f1
                            //            01:  f8
                            //            10:  f32
                            //            11:  fc32

    ONSF    |= 0xC0;        // XX-- ----
                            // |+-------- timer A0 event/trigger select bits
                            // +--------- timer A0 event/trigger select bits
                            //            00:  input on TA0in (must be input)
                            //            01:  overflow of timer B2
                            //            10:  overflow of timer A4
                            //            11:  overflow of timer A1

    // Clock prescaler reset flag
    // This function is only effective if fc32 is selected
    if ((TA0MR & 0xC0)==0xC0)
    {
        CPSRF = 0x80;       // 1--- ----                                   
                            // +---------- 1: clock prescaler is reset 
    }
}

/**************************************************************************/
/*                                                                        */
/*       Timer A0 - start                                                 */
/*       In following cases this routine takes no effect:                 */
/*       - in one-shot timer mode if ext. trigger or timer overflow is    */
/*         selected as start condition                                    */
/*       - in pwm mode if external trigger or timer overflow is selected  */
/*         as start condition                                             */
/*                                                                        */
/*       Name         :      timer_a0_start                               */
/*       Date/Author  :      08.04.1997/ST                                */
/*       Parameter    :                                                   */
/*       Return       :                                                   */
/*                                                                        */
/**************************************************************************/
void near timer_a0_start (void)
{
    TABSR |= 0x01;          // ---- ---1
                            //         +- 1: start timer A0 (count flag)

    ONSF  |= 0x01;          // ---- ---1
                            //         +- 1: start timer A0 (one-shot flag)
}

/**************************************************************************/
/*                                                                        */
/*       Timer A0 - stop                                                  */
/*       In following cases this routine takes no effect:                 */
/*       - in one-shot timer mode if ext. trigger or timer overflow is    */
/*         selected as start condition                                    */
/*       - in pwm mode if external trigger or timer overflow is selected  */
/*         as start condition                                             */
/*                                                                        */
/*       Name         :      timer_a0_stop                                */
/*       Date/Author  :      08.04.1997/ST                                */
/*       Parameter    :                                                   */
/*       Return       :                                                   */
/*                                                                        */
/**************************************************************************/
void near timer_a0_stop (void)
{
    TABSR &= ~(0x01);           // ---- ---0
                                //         +- 0: stop  timer A0 (count flag)

    ONSF  &= ~(0x01);           // ---- ---0
                                //         +- 0: stop  timer A0 (one-shot flag)
}

/**************************************************************************/
/*                                                                        */
/*       Timer A0 - get current value                                     */
/*                                                                        */
/*       Name         :      timer_a0_get                                 */
/*       Date/Author  :      08.04.1997/ST                                */
/*       Parameter    :                                                   */
/*       Return       :      - current count value in timer mode or event */
/*                             counter mode                               */
/*                           - indeterminate in one-shot mode or pwm mode */
/*                                                                        */
/**************************************************************************/
unsigned int near timer_a0_get (void)
{
    return(TA0);
}

/**************************************************************************/
/*                                                                        */
/*       timer A0 - set current value                                     */
/*       when counting stopped    : write value to reload register and    */
/*                                  counter                               */
/*       when counting in progress: write value only to reload register   */
/*                                  transferred to counter at next reload */
/*                                  time                                  */
/*       In 8-bit pwm mode highbyte gives time of high level and          */
/*                         lowbyte gives time of low level                */
/*                                                                        */
/*       Name         :      timer_a0_set                                 */
/*       Date/Author  :      08.04.1997/ST                                */
/*       Parameter    :      load value                                   */
/*       Return       :                                                   */
/*                                                                        */
/**************************************************************************/
void near timer_a0_set (unsigned int value)
{
    TA0 = value;
}


/**************************************************************************/
/*                                                                        */
/*       Timer A0 - set interrupt                                         */
/*       user must adapt interrupt priority level                         */
/*                                                                        */
/*       Name         :      timer_a0_interrupt_set                       */
/*       Date/Author  :      14.04.1997/ST                                */
/*       Parameter    :                                                   */
/*       Return       :                                                   */
/*                                                                        */
/**************************************************************************/
void near timer_a0_interrupt_set (void)
{
    TA0IC = 0x01;           // ---- XXXX
                            //      ||||
                            //      |||+-- Interupt priority level select bit
                            //      ||+--- Interupt priority level select bit
                            //      |+---- Interupt priority level select bit
                            //      |      000: Level 0 (interrupt disabled)
                            //      |      001: Level 1
                            //      |      010: Level 2
                            //      |      011: Level 3
                            //      |      100: Level 4
                            //      |      101: Level 5
                            //      |      110: Level 6
                            //      |      111: Level 7
                            //      +----- Interupt request bit 
                            //             0: Interrupt not requested
                            //             1: Interrupt requested
}

/**************************************************************************/
/*                                                                        */
/*       Timer A0 - clear interrupt                                       */
/*                                                                        */