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/** @file tdmdemo1.c
@author M. P. Hayes, UCECE
@date 10 August 2011
@brief Time division multiplexing of display demo
@defgroup tdmdemo1 Time division multiplexing of display demo
*/
#include "system.h"
#include "pacer.h"
#include "ledmat.h"
/* Define polling rate in Hz. */
#define LOOP_RATE 1000
/* Define display refresh rate in Hz. */
#define REFRESH_RATE 1
#define UPDATE_PERIOD (LOOP_RATE / (LEDMAT_COLS_NUM * REFRESH_RATE))
int main (void)
{
uint8_t col = 0;
uint8_t tick = 0;
system_init ();
ledmat_init ();
pacer_init (LOOP_RATE);
/* Paced loop. */
while (1)
{
/* Wait for next tick. */
pacer_wait ();
tick++;
if (tick >= UPDATE_PERIOD)
{
tick = 0;
/* Display an 'H' character by time division multiplexing
the columns of the LED matrix. */
switch (col)
{
case 0:
ledmat_display_column (0x7f, 0);
break;
case 1:
ledmat_display_column (0x08, 1);
break;
case 2:
ledmat_display_column (0x08, 2);
break;
case 3:
ledmat_display_column (0x08, 3);
break;
case 4:
ledmat_display_column (0x7f, 4);
break;
default:
break;
}
col++;
if (col >= LEDMAT_COLS_NUM )
col = 0;
}
}
return 0;
}