what is the concept of moving message display

"guidance about moving message display"

Maybe just take a static message display and put wheels on it?

"guidance about moving message display"

Maybe just take a static message display and put wheels on it?

Here's the code. It's not tested, certainly not guaranteed, and may not even work in your system.

#define DISPLAY_LEN 12

extern void display_char (
  char c, unsigned char pos);

void moving_message (
  char *new_msg)
{
static unsigned int index;
static unsigned int len;
static char *message;

unsigned char i;

if (new_msg == NULL)
  {
  index = 0;
  message = new_msg;
  len = strlen (message);
  }

for (i = 0; i<DISPLAY_LEN; i++)
  {
  display_char (message[(i+index)%len], i);
  }

index = (index+1)%len;
}

Thanks for your support sorry I do not mention that I am working on Dot Matrics 7x5(Total of 19 Matric attached with
89c51 & 74164 I sent a single character on display which is clearly visible on serially connected matrics with 74164 on second time when I sent 00 data and again sent data on matrics, it break the data on dot matrics.

Kindly Guide me for this and how can I send u my code which is on assembly language.

Thanks
AFZAAL BAIG