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GP32 demo code (offscr)

sang's profile picture
Published in 
GP32
 · 9 months ago

This simple demo demonstrates vertical scrolling using virtual screens and changing frame buffer pointers.

This demo bangs the hardware bypassing the BIOS (tested with 157e FW).

offscr.c

// (c) 13-Jul-2002 Jouni 'Mr.Spiv' Korhonen 
//

#include "gpdef.h"
#include "gpstdlib.h"
#include "gpgraphic.h"
#include "gpmain.h"
#include "gpfont.h"

#include <stdlib.h>
#include <string.h>

// strcoll, ptrdiff_t, memcmp, strspn strerror

GPDRAWSURFACE gpDraw;
GPDRAWTAG gpDrawTag;

volatile long* tpal = (long*)0x14a00050;
volatile long* lcdcon1 = (long*)0x14a00000;
volatile long* lcdcon2 = (long*)0x14a00004;
volatile long* lcdcon3 = (long*)0x14a00008;
volatile long* lcdcon4 = (long*)0x14a0000c;
volatile long* lcdcon5 = (long*)0x14a00010;

volatile long* lcdaddr1 = (long*)0x14a00014;
volatile long* lcdaddr2 = (long*)0x14a00018;
volatile long* lcdaddr3 = (long*)0x14a0001c;


volatile long* hwpal = (long*)0x14a00400;

extern unsigned char BK_Pic_c[];

//
//
//

void waitline( int line ) {
while (line != ((*lcdcon1 >> 18) & 0x1ff) );
}


//
//
//
//
//

void GpMain(void *arg)
{
long scrptru;
long scrptrl, scrptrl2;
long ptr;
char buf[100];
int m,n;

unsigned short *dst;
unsigned short *src;


volatile unsigned long *gpb = (unsigned long *)0x1560000c;
volatile unsigned long *gpe = (unsigned long *)0x15600030;

//

//GpGraphicModeSet(GPC_DFLAG_16BPP,NULL);
//*lcdcon5 |= 1;
//GpLcdSurfaceGet(&gpDraw, 0);
//GpRectFill(NULL, &gpDraw, 0, 0, gpDraw.buf_w, gpDraw.buf_h, 0x01);

//
//dst = (unsigned short*)gpDraw.ptbuffer;
dst = (unsigned short*)0x0C7B4000;
src = (unsigned short*)BK_Pic_c;

for (m = 0; m < 320; m++) {
for (n = 0; n < 240; n++) {
*dst++ = *src++;
}
for (n = 0; n < 240; n++) {
*dst = dst[-240];
dst++;
}
}


//gm_sprintf(buf,"src: %08x, dst: %08x",src,dst);
//GpTextOut(NULL,&gpDraw,10,120,buf,0xaa);


//GpSurfaceSet(&gpDraw); //gpDraw primary surface· setting

// 320x240x16 screen mode, 0 pixel offscreen
// expects 33MHz HCLK
#if 1
*lcdcon1 = ((3 << 8) | (0 << 7) | (3 << 5) | (12 << 1) | (0));
// CLKVAL=3, VNMODE=0, PNRMODE=TFT, BPPMODE=1100 (16bits), ENDID=0
*lcdcon2 = ((1 << 24) | (319 << 14) | (2 << 6) | 1);
// VBPD=1, LINEVAL=319, VFPD=2, VSPW=1
*lcdcon3 = ((6 << 19) | (239 << 8) | (2));
// HBPD=6, HOZVAL=239, HFPD=2
*lcdcon4 = ((0 << 24) | (0 << 16) | (4));
// PALADDEN=0, ADDVAL=0, HSPW=4
*lcdcon5 = ((1 << 10) | (1 << 9) | (1 << 8) | (0 << 7) | (0 << 6) | (0 << 4) | (0 << 2) | (1));
// INVVCLK=1, INVVLINE=1, INVVFRAME=1, INVVD=0, INVVDEN=0
// INVENDLINE=0, ENLEND=0, BSWP=0, HWSWP=1
*tpal = 0;

ptr = (long)0x0C7B4000;
*lcdaddr1 = ((ptr & 0x0fc00000) >> 1) | ((ptr & 0x3ffffe) >> 1);
*lcdaddr2 = ((ptr & 0x003ffffe) >> 1) + (240+240) * (319+1);

*lcdaddr3 = ((240 << 11) | (240));
// OFFSIZE=0, PAGEWIDTH=240 halfwords -> 240 pixels

*lcdcon1 |= 1; // enable lcd
#endif


//
scrptru = *lcdaddr1;
//scrptrl = *lcdaddr2;
//scrptrl = *lcdaddr2 - 240;
//scrptrl = *lcdaddr2 - 240*2;
scrptrl = *lcdaddr2;

n = 0;
m = 0;

while ((GpKeyGet() & (GPC_VK_FL | GPC_VK_FR)) != (GPC_VK_FL | GPC_VK_FR)) {
long reg, reg2;

waitline(2);

if (n++ == 240) {
*lcdaddr1 = scrptru;
*lcdaddr2 = scrptrl;
n = 0;
} else {
*lcdaddr1 += 1;
*lcdaddr2 += 1;
}

waitline(1);


}


*tpal = 0x0001ffff;
// reboot..

while ((GpKeyGet() & (GPC_VK_SELECT | GPC_VK_START)) != (GPC_VK_SELECT | GPC_VK_START));
GpAppExit();
}

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