I have been playing.... I have created a 8x32 LED array with row scanning... I have still used interrupts but I am scanning exactly the same way as the T6963C controller scans the LCD. I can change pixel by pixel and draw animations
https://www.youtube.com/watch?v=6UmvOTKGY7Q&feature=youtu.be
It looks laggy but that isn't how it is I can't produce decent video's.
This way you can draw to the screen just as we do for the larger screen..
Here is the code..
Thre are two external files ... The animation and the font... The font is slightly different as the screen writes are for row orientation..
https://www.youtube.com/watch?v=6UmvOTKGY7Q&feature=youtu.be
It looks laggy but that isn't how it is I can't produce decent video's.
This way you can draw to the screen just as we do for the larger screen..
Here is the code..
Code:
#include<pic.h>
#define _XTAL_FREQ 20000000L // 20 meg crsytal
__CONFIG(0x3F52); // HS on, WDT off, BOR on, PWRTon..
char displayPointer=0; // for interrupt use...
extern const char fnt[]; // Font in external C file
extern const char anim[];
unsigned char buffer[32]; // buffer for screen
unsigned char backbuffer[32]; // Spare screen for drawing on
char pow[8]={128,64,32,16,8,4,2,1};
void interrupt ISR() // This just swaps the buffer to the display
{
if(TMR2IF) // Make sure its the timer interrupt.
{
PORTB = 0; // Clear old data first
if(displayPointer == 0 ) // 1st frame..
RC4 = 1; // Data = 1 on the first clock only
RC3 = 1;
__delay_us(20); // Clock the shift registers
RC3 = 0;
RC4 = 0; // Make sure data stays low for the rest of the cycles
PORTB = buffer[displayPointer]; // Move buffer row by row( 4 row sections per row )
if(++displayPointer==32) // 32 LED row sections in total
displayPointer = 0; // Back to first row..
}
TMR2IF = 0; // Clear timer 2 interrupt flag
}
void pixel(signed char x,signed char y,int cond)
{
int tmp;
char pix,msk;
if(x<0 || y<0) return; // outside drawing limits negative
if(x>31 || y>7) return; // outside drawing limits positive
tmp = (y << 2) + (x>>3); // Linear position
pix = x%8; // pixel required
pix = pow[ pix];
msk = backbuffer[tmp]; // get exsisting data
if(cond == 2)
pix ^= msk; // XOR data to screen
if (cond == 1)
{
pix = ~pix;
pix &= msk; // AND data to screen
}
if(cond == 0)
pix |= msk; // OR data to screen
backbuffer[tmp] = pix; // apply changes
}
void charput(char ch, signed char x,signed char y)
{
signed char x1, y1;
const char* addr2; // pointer to character
char disp;
ch -= 0x20; // characters starts a 0 not 0x20
addr2 = &fnt[0]; // start of font array
addr2 = addr2 + ((int)ch * 8); // start place in font array
for( y1=0;y1<8;y1++) // eight rows
{
disp = *addr2;
for (x1 = 0; x1<8; x1++) // eight pixels
{
if(disp & pow[x1])
pixel(x+x1,y+y1,0); // OR the pixel to the display buffer
}
addr2++;
}
}
void strput(const char* ch, signed char x,signed char y)
{
int addr;
while (*ch )
{
charput(*ch++,x,y); // write a string to the display buffer
x+=7;
}
}
void clr()
{
int addr;
for(addr=0;addr<32;addr++) // Empty display buffer
backbuffer[addr]= 0;
}
void Blit()
{
int addr=0;
GIE = 0;
for(addr=0;addr < 32;addr ++)
{
buffer[addr] = backbuffer[addr]; // put all data from display buffer
} // to screen buffer
GIE = 1;
}
void animation(void)
{
char x,y;
const char* frame; // pointer to frames
for(x=0;x<14;x++) // 14 frames in animation
{
clr(); // clears the display buffer
frame = &anim[0]; // start of frames
frame += x*32; // each frame is 32 bytes long
for(y=0;y<32;y++)
backbuffer[y] = *frame++; // Cycle through the animation
Blit(); // pass to screen buffer
__delay_ms(200); // time to view
}
}
void displaystring(void) // this routine prints through the screen buffer
{ // moving one pixel at a time
signed char x=32,y=0; // I made these signed so I could print
for(y = 0;y < 96 ;y++) // to nowhere so I could produce the scrolling effect
{
clr(); // Clear the display buffer
strput("HELLO WORLD!!",x--,0); // adjust the scrolling string
Blit(); // pass to screen buffer
__delay_ms(100); // time to view
}
}
void main(void)
{
int s;
ADCON1 = 0x6; // ALL digital
T2CON = 0x1e; // T2 on, 16:1 pre scale
PR2 = 109; // timer preload value ( equates to 1.4mS with 20mhz crystal)
TMR2IE = 1; // enable timer 2 interrupt
PEIE = 1; // enable peripheral interrupt
GIE = 1; // enableglobal interrupt
TRISB = 0; // Port B as output...
TRISC = 0; // Port C as ouput...
animation();
displaystring();
while(1)
{
clr();
if(s==0) strput("LOL",0,0); // Here's the message
if(s==1) strput(" LOL",0,0);
if(++s == 2) s=0;
__delay_ms(500);
Blit();
}
} // End mainThre are two external files ... The animation and the font... The font is slightly different as the screen writes are for row orientation..
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