?? sevensegment.c
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/*
*********************************************************************************************************
* Wytec Dragon12 Board Support Package
* File : SevenSegDisp_BSP.c
* By : Eric Shufro
*
* Notes: This file provides thread safe software support for driving the 7-Segment
* LED display blocks on a Wytec Dragon12.
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* INCLUDES
*********************************************************************************************************
*/
#include <includes.h>
/*
*********************************************************************************************************
* 7-SEGMENT DISPLAY CONSTANT DATA
*********************************************************************************************************
*/
#define SSD_0 0x3F /* Seven segment display, character '0' */
#define SSD_1 0x06 /* Seven segment display, character '1' */
#define SSD_2 0x5B /* Seven segment display, character '2' */
#define SSD_3 0x4F /* Seven segment display, character '3' */
#define SSD_4 0x66 /* Seven segment display, character '4' */
#define SSD_5 0x6D /* Seven segment display, character '5' */
#define SSD_6 0x7D /* Seven segment display, character '6' */
#define SSD_7 0x07 /* Seven segment display, character '7' */
#define SSD_8 0x7F /* Seven segment display, character '8' */
#define SSD_9 0x6F /* Seven segment display, character '9' */
#define SSD_A 0x77 /* Seven segment display, character 'A' */
#define SSD_B 0x7F /* Seven segment display, character 'B' */
#define SSD_C 0x39 /* Seven segment display, character 'C' */
#define SSD_D 0x5E /* Seven segment display, character 'D' */
#define SSD_E 0x59 /* Seven segment display, character 'E' */
#define SSD_F 0x71 /* Seven segment display, character 'F' */
/*
*********************************************************************************************************
* GLOBALS
*********************************************************************************************************
*/
static INT16U nbrCnts; /* Holds the number of timer increments for the 7-Seg Disp */
static INT16U outputNum; /* Holds the number between 0000 and 9999 to be displayed */
static INT8U actBlockNum; /* Holds the number of the active 7-Segment LED Block (0-3) */
/*
*********************************************************************************************************
* PROTOTYPES
*********************************************************************************************************
*/
static void SevenSegOut(INT8U digit); /* Internal function for writing to the 7-Seg Disp data bus */
/*
*********************************************************************************************************
* SEVEN SEGMENT DISPLAY INIT
*
* Description : This function initializes the 7-Segment Enable I/O pins as Outputs, and
* configures one of the ECT Output Compare channels to create a periodic
* interrupt that is used to switch the active 7-Segment LED block and
* the corresponding number to be displayed.
*
* Arguments : None
*
* Returns : None
*
* Notes : THE CORRECT ECT CHANNEL ISR VECTOR MUST BE SET WITHIN VECTORS.C.
* This involves plugging the right vector number with the name of
* the ISR function below. A prototype at the top of vectors.c must
* also be created.
*********************************************************************************************************
*/
void SevenSegDisp_Init (void)
{
INT32U cpu_frq;
INT32U bus_frq;
INT8U ECT_Prescaler;
DDRP |= 0x0F; /* Set the 7-Segment Enable I/O pins to output */
actBlockNum = 0; /* Set display 0 as the first active LED display block */
cpu_frq = BSP_CPU_ClkFreq(); /* Get the current CPU frequency */
bus_frq = cpu_frq / 2; /* Derive the BUS frequency from the CPU frequency */
ECT_Prescaler = TSCR2 & 0x07; /* Get the prescaler value in the control register */
ECT_Prescaler = (1 << ECT_Prescaler); /* Calculate the correct prescaler value from the reg val */
/* Calculate the # of ticks for an interrupt period of 1ms */
nbrCnts = (INT16U)((bus_frq / (ECT_Prescaler * 225)) - 1); /* 225 represents 225 ticks in 1 second, each tick ~4ms */
#if SEVEN_SEG_OC == 0
TIOS |= 0x01; /* Make channel an output compare */
TC0 = TCNT + nbrCnts; /* Set TC0 to present time + nbrCnts */
TIE |= 0x01; /* Enable OC0 interrupt. */
#endif
#if SEVEN_SEG_OC == 1
TIOS |= 0x02; /* Make channel an output compare */
TC1 = TCNT + nbrCnts; /* Set TC1 to present time + nbrCnts */
TIE |= 0x02; /* Enable OC1 interrupt. */
#endif
#if SEVEN_SEG_OC == 2
TIOS |= 0x04; /* Make channel an output compare */
TC2 = TCNT + nbrCnts; /* Set TC2 to present time + nbrCnts */
TIE |= 0x04; /* Enable OC2 interrupt. */
#endif
#if SEVEN_SEG_OC == 3
TIOS |= 0x08; /* Make channel an output compare */
TC3 = TCNT + nbrCnts; /* Set TC3 to present time + nbrCnts */
TIE |= 0x08; /* Enable OC3 interrupt. */
#endif
#if SEVEN_SEG_OC == 4
TIOS |= 0x10; /* Make channel an output compare */
TC4 = TCNT + nbrCnts; /* Set TC4 to present time + nbrCnts */
TIE |= 0x10; /* Enable OC4 interrupt. */
#endif
#if SEVEN_SEG_OC == 5
TIOS |= 0x20; /* Make channel an output compare */
TC5 = TCNT + nbrCnts; /* Set TC5 to present time + nbrCnts */
TIE |= 0x20; /* Enable OC5 interrupt. */
#endif
#if SEVEN_SEG_OC == 6
TIOS |= 0x40; /* Make channel an output compare */
TC6 = TCNT + nbrCnts; /* Set TC6 to present time + nbrCnts */
TIE |= 0x40; /* Enable OC6 interrupt. */
#endif
#if SEVEN_SEG_OC == 7
TIOS |= 0x80; /* Make channel an output compare */
TC7 = TCNT + nbrCnts; /* Set TC7 to present time + nbrCnts */
TIE |= 0x80; /* Enable OC7 interrupt. */
#endif
TSCR1 = 0xC0; /* Enable counter & disable counter in background mode */
}
/*
*********************************************************************************************************
* SEVEN SEGMENT INTERRUPT SERVICE ROUTINE
*
* Description : This function is the 7-Segment LED Interrupt Service Routine. This
* interrupt occurs periodically at the rate configured within
* sevenSegDisp_Init(). Each time the interrupt occurs, the active
* LED block is changed, and the value on the 7-Segment LED data
* bus is updated.
*
* Arguments : None
*
* Returns : None
*
* Notes : THE CORRECT ECT CHANNEL ISR VECTOR MUST BE SET WITHIN VECTORS.C.
* This involves plugging the right vector number with the name of
* the ISR function below. A prototype at the top of vectors.c must
* also be created.
*********************************************************************************************************
*/
void SevenSegDisp_ISR_Handler (void)
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