X-Git-Url: http://4ch.mooo.com/gitweb/?a=blobdiff_plain;f=src%2Flib%2F16_vl.c;h=652ef89c2491b898bd25908b6d63c70f5bee7504;hb=6cfcd9ddd5f8b515913ea6f0e0f84f8e4c0fb720;hp=9369ce49ab7b2c2e88c086962684dae117fd00c0;hpb=4ecf82fc48a4a19ff72cd89bce7d0bda18cf2f0c;p=16.git

diff --git a/src/lib/16_vl.c b/src/lib/16_vl.c
index 9369ce49..652ef89c 100755
--- a/src/lib/16_vl.c
+++ b/src/lib/16_vl.c
@@ -369,6 +369,37 @@ modexShowPage_(page_t *page)
 	outp(AC_INDEX, (page->dx & 0x03) << 1);
 }
 
+void
+modexShowPageVsync(page_t *page) {
+	word high_address, low_address, offset;
+	byte crtcOffset;
+
+	/* calculate offset */
+	offset = (word) page->data;
+	offset += page->dy * (page->width >> 2 );
+	offset += page->dx >> 2;
+
+	/* calculate crtcOffset according to virtual width */
+	crtcOffset = page->width >> 3;
+
+	high_address = HIGH_ADDRESS | (offset & 0xff00);
+	low_address  = LOW_ADDRESS  | (offset << 8);
+
+	/* wait for appropriate timing and then program CRTC */
+	while ((inp(INPUT_STATUS_1) & DISPLAY_ENABLE));
+	outpw(CRTC_INDEX, high_address);
+	outpw(CRTC_INDEX, low_address);
+	outp(CRTC_INDEX, 0x13);
+	outp(CRTC_DATA, crtcOffset);
+
+	/* wait for one retrace */
+	while (!(inp(INPUT_STATUS_1) & VRETRACE));
+
+	/* do PEL panning here */
+	outp(AC_INDEX, 0x33);
+	outp(AC_INDEX, (page->dx & 0x03) << 1);
+}
+
 void
 modexPanPage(page_t *page, int dx, int dy) {
 	page->dx = dx;