Update vdu.asm

6 years ago · 11857925d2
1 changed files with 32 additions and 54 deletions
--- a/Source/HBIOS/vdu.asm
+++ b/Source/HBIOS/vdu.asm
@ -567,12 +567,33 @@ VDU_POS		.DW 	0		; CURRENT DISPLAY POSITION
 VDU_OFFSET	.DW 	0		; CURRENT DISPLAY POSITION
 VDU_BUF		.FILL	256,0		; COPY BUFFER
 ;
+;==================================================================================================
+;   ECB-VDU VIDEO MODE DESCRIPTION
+;==================================================================================================\
+;
+; CCIR 625/50 VERSION (USED IN MOST OF THE WORLD)
+; JUMPER K1 2-3, K2 1-2 FOR 2MHz CHAR CLOCK
+;
+; THE CCIR 625/50 TELEVISION STANDARD HAS 625 LINES INTERLACED AT 50 FIELDS PER SECOND.  THIS WORKS 
+; OUT AS 50 FIELDS OF 312.5 LINES PER SECOND NON-INTERLACED AS USED HERE.
+; HORIZONTAL LINE WIDTH IS 64uS.  FOR A 2 MHz CHARACTER CLOCK (R0+1)/2000000 = 64uS
+; NEAREST NUMBER OF LINES IS 312 = (R4+1) * (R9+1) + R5.
+; 15625 / 312 = 50.08 FIELDS PER SECOND (NEAR ENOUGH-DGG)
+;
+;
+;	.DB	078H			; R8 MODE	B7=0	TRANSPARENT UPDATE DURING BLANKING
+;					;		B6=1	PIN 34 IS UPDATE STROBE
+;					;		B5=1	DELAY CURSOR 1 CHARACTER
+;					;		B4=1	DELAY DISPLAY ENABLE 1 CHARACTER
+;					;		B3=1	TRANSPARENT MEMORY ADDRESSING
+;					;		B2=0	RAM STRAIGHT BINARY ADDRESSING
+;					;		B1,B0=0	NON-INTERLACE
+VDU_INIT6845:
 #IF	(VDUSIZ=V80X24)
 ;==================================================================================================
 ;   VDU DRIVER - SY6845 REGISTER INITIALIZATION -80x24 10x8
 ;==================================================================================================
 ;
-VDU_INIT6845:
 	.DB	07FH			; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
 	.DB	DROWS			; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED (80 COLUMNS)
 	.DB	060H			; R2 HORIZONTAL SYNC POSITION
@ -581,13 +602,7 @@ VDU_INIT6845:
 	.DB	002H			; R5 VERTICAL TOTAL ADJUST (
 	.DB	DLINES			; R6 VERTICAL DISPLAYED (24 ROWS)
 	.DB	01AH			; R7 VERTICAL SYNC
-	.DB	078H			; R8 MODE	B7=0 TRANSPARENT UPDATE DURING BLANKING
-					;		B6=1 PIN 34 IS UPDATE STROBE
-					;		B5=1 DELAY CURSOR 1 CHARACTER
-					;		B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
-					;		B3=1 TRANSPARENT MEMORY ADDRESSING
-					;		B2=0 RAM STRAIGHT BINARY ADDRESSING
-					;		B1,B0=0 NON-INTERLACE
+	.DB	078H			; R8 MODE
 	.DB	DSCANL-1		; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
 	.DB	VDU_R10			; R10 CURSOR START RASTER
 	.DB	VDU_R11			; R11 CURSOR END RASTER
@ -595,13 +610,12 @@ VDU_INIT6845:
 	.DB	00H			; R13 START ADDRESS LO
 	.DB	00H			; R14 CURSOR ADDRESS HI
 	.DB	00H			; R15 CURSOR ADDRESS LO
-;
 #ENDIF
 #IF	(VDUSIZ=V80X25)
 ;==================================================================================================
 ;   VDU DRIVER - SY6845 REGISTER INITIALIZATION -80x25 10x8
 ;==================================================================================================
-VDU_INIT6845:
+;
 	.DB	07FH			; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
 	.DB	DROWS			; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED =80
 	.DB	060H			; R2 HORIZONTAL SYNC POSITION
@ -610,13 +624,7 @@ VDU_INIT6845:
 	.DB	002H			; R5 VERTICAL TOTAL ADJUST (
 	.DB	DLINES			; R6 VERTICAL DISPLAYED (25 ROWS)
 	.DB	01BH			; R7 VERTICAL SYNC
-	.DB	078H			; R8 MODE	B7=0 TRANSPARENT UPDATE DURING BLANKING
-;					;		B6=1 PIN 34 IS UPDATE STROBE
-;					;		B5=1 DELAY CURSOR 1 CHARACTER
-;					;		B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
-;					;		B3=1 TRANSPARENT MEMORY ADDRESSING
-;					;		B2=0 RAM STRAIGHT BINARY ADDRESSING
-;					;		B1,B0=0 NON-INTERLACE
+	.DB	078H			; R8 MODE
 	.DB	DSCANL-1		; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
 	.DB	VDU_R10			; R10 CURSOR START RASTER
 	.DB	VDU_R11			; R11 CURSOR END RASTER
@ -624,13 +632,12 @@ VDU_INIT6845:
 	.DB	00H			; R13 START ADDRESS LO
 	.DB	00H			; R14 CURSOR ADDRESS HI
 	.DB	00H			; R15 CURSOR ADDRESS LO
-;
 #ENDIF
 #IF	(VDUSIZ=V80X30)
 ;==================================================================================================
 ;   VDU DRIVER - SY6845 REGISTER INITIALIZATION -80x30 8x8
 ;==================================================================================================
-VDU_INIT6845:
+;
 	.DB	07FH			; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
 	.DB	DROWS			; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED =80
 	.DB	060H			; R2 HORIZONTAL SYNC POSITION
@ -639,13 +646,7 @@ VDU_INIT6845:
 	.DB	00H			; R5 VERTICAL TOTAL ADJUST (
 	.DB	DLINES			; R6 VERTICAL DISPLAYED (30 ROWS)
 	.DB	22H			; R7 VERTICAL SYNC
-	.DB	078H			; R8 MODE	B7=0 TRANSPARENT UPDATE DURING BLANKING
-;					;		B6=1 PIN 34 IS UPDATE STROBE
-;					;		B5=1 DELAY CURSOR 1 CHARACTER
-;					;		B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
-;					;		B3=1 TRANSPARENT MEMORY ADDRESSING
-;					;		B2=0 RAM STRAIGHT BINARY ADDRESSING
-;					;		B1,B0=0 NON-INTERLACE
+	.DB	078H			; R8 MODE
 	.DB	DSCANL-1		; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
 	.DB	VDU_R10			; R10 CURSOR START RASTER
 	.DB	VDU_R11			; R11 CURSOR END RASTER
@ -653,13 +654,12 @@ VDU_INIT6845:
 	.DB	00H			; R13 START ADDRESS LO
 	.DB	00H			; R14 CURSOR ADDRESS HI
 	.DB	00H			; R15 CURSOR ADDRESS LO
-;
 #ENDIF
 #IF	(VDUSIZ=V80X25B)
 ;==================================================================================================
 ;   VDU DRIVER - SY6845 REGISTER INITIALIZATION -80x25 12x8 TO SUIT BLOCK GRAPHICS
 ;==================================================================================================
-VDU_INIT6845:
+;
 	.DB	07FH			; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
 	.DB	DROWS			; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED =80
 	.DB	060H			; R2 HORIZONTAL SYNC POSITION
@ -668,13 +668,7 @@ VDU_INIT6845:
 	.DB	00H			; R5 VERTICAL TOTAL ADJUST (312-(R4+1)*DSCANL)
 	.DB	DLINES			; R6 VERTICAL DISPLAY 
 	.DB	019H			; R7 VERTICAL SYNC  (DLINES .. R4)
-	.DB	078H			; R8 MODE	B7=0 TRANSPARENT UPDATE DURING BLANKING
-;					;		B6=1 PIN 34 IS UPDATE STROBE
-;					;		B5=1 DELAY CURSOR 1 CHARACTER
-;					;		B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
-;					;		B3=1 TRANSPARENT MEMORY ADDRESSING
-;					;		B2=0 RAM STRAIGHT BINARY ADDRESSING
-;					;		B1,B0=0 NON-INTERLACE
+	.DB	078H			; R8 MODE
 	.DB	DSCANL-1		; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
 	.DB	VDU_R10			; R10 CURSOR START RASTER
 	.DB	VDU_R11			; R11 CURSOR END RASTER
@ -682,13 +676,12 @@ VDU_INIT6845:
 	.DB	00H			; R13 START ADDRESS LO
 	.DB	00H			; R14 CURSOR ADDRESS HI
 	.DB	00H			; R15 CURSOR ADDRESS LO
-;
 #ENDIF
 #IF	(VDUSIZ=V80X24B)
 ;==================================================================================================
 ;   VDU DRIVER - SY6845 REGISTER INITIALIZATION -80x24 12x8 TO SUIT BLOCK GRAPHICS
 ;==================================================================================================
-VDU_INIT6845:
+;
 	.DB	07FH			; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
 	.DB	DROWS			; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED =80
 	.DB	060H			; R2 HORIZONTAL SYNC POSITION
@ -697,13 +690,7 @@ VDU_INIT6845:
 	.DB	00H			; R5 VERTICAL TOTAL ADJUST (312-(R4+1)*DSCANL)
 	.DB	DLINES			; R6 VERTICAL DISPLAY 
 	.DB	018H			; R7 VERTICAL SYNC  (DLINES .. R4)
-	.DB	078H			; R8 MODE	B7=0 TRANSPARENT UPDATE DURING BLANKING
-;					;		B6=1 PIN 34 IS UPDATE STROBE
-;					;		B5=1 DELAY CURSOR 1 CHARACTER
-;					;		B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
-;					;		B3=1 TRANSPARENT MEMORY ADDRESSING
-;					;		B2=0 RAM STRAIGHT BINARY ADDRESSING
-;					;		B1,B0=0 NON-INTERLACE
+	.DB	078H			; R8 MODE
 	.DB	DSCANL-1		; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
 	.DB	VDU_R10			; R10 CURSOR START RASTER
 	.DB	VDU_R11			; R11 CURSOR END RASTER
@ -713,17 +700,8 @@ VDU_INIT6845:
 	.DB	00H			; R15 CURSOR ADDRESS LO
 ;
 #ENDIF
-; CCIR 625/50 VERSION (USED IN MOST OF THE WORLD)
-; JUMPER K1 2-3, K2 1-2 FOR 2MHz CHAR CLOCK
 ;
-; THE CCIR 625/50 TELEVISION STANDARD HAS 625 LINES INTERLACED AT 50 FIELDS PER SECOND.  THIS WORKS 
-; OUT AS 50 FIELDS OF 312.5 LINES PER SECOND NON-INTERLACED AS USED HERE.
-; HORIZONTAL LINE WIDTH IS 64uS.  FOR A 2 MHz CHARACTER CLOCK (R0+1)/2000000 = 64uS
-; NEAREST NUMBER OF LINES IS 312 = (R4+1) * (R9+1) + R5.
-; 15625 / 312 = 50.08 FIELDS PER SECOND (NEAR ENOUGH-DGG)
-;
-;
-;==================================================================================================
+;;==================================================================================================
 ;   VDU DRIVER - INSTANCE DATA
 ;==================================================================================================
 ;