Working EOL

pat80-io-devices/composite-pal-adapter/software/avr-assembly/character_generator.asm

@@ -48,7 +48,7 @@ draw_char:
 	; Char drawing is complete. Increment cursor position
 	inc POS_COLUMN
 	; Check if end of line
-	cpi POS_COLUMN, 52
+	cpi POS_COLUMN, LINE_COLUMNS
 	breq draw_char_eol
 	; Reset chunk position to first glyph line of next column
 	mov YL, r2	; first restore Y
@@ -63,7 +63,7 @@ draw_char:
 		brne draw_char_end
 		cpi YL, low(FRAMEBUFFER_END + 1)
 		brne draw_char_end
-		; End of screen reached! Scroll framebuffer by 1 line (=52*FONT_HEIGHT bytes)
+		; End of screen reached! Scroll framebuffer by 1 line (=46*FONT_HEIGHT bytes)
 		; TODO
 	draw_char_end:
 		ret

pat80-io-devices/composite-pal-adapter/software/avr-assembly/communication.asm

@@ -9,7 +9,7 @@
 ; INTERNAL POINTER:
 ; Internally, the last screen position is represented by 24 bits in two registers:
 ; POS_COARSE: Register Y (16-bit, r31 and r30): Coarse position. Points to one of the chunks
-;    (character columns). 52 chunks per row, 304 rows. Used for character position, as
+;    (character columns). 46 chunks per row, 304 rows. Used for character position, as
 ;    1 chunk = 1 byte = 1 character.
 ; POS_FINE: Register r24: Fine position. Represents the bit inside the chunk selected by POS_COARSE.
 ;    Ignored in character mode (the character is always aligned to column). Used in graphic mode.

pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm

@@ -26,8 +26,8 @@
 
 ; *** reserved registers ***
 ; Cursor Position
-;     POS_COLUMN (0-103) represents the column on a pair of rows: 0 to 51 is the first row, 52 to 103 the second one
+;     POS_COLUMN (0-103) represents the column on a pair of rows: 0 to 46 is the first row, 47 to 92 the second one
-;     POS_ROWP (0-152) represent the pair of rows. POS_ROWP = 5 means the 10th and 11th rows
+;     POS_ROWP (0-128) represent the pair of rows. POS_ROWP = 5 means the 10th and 11th rows
 ;     POS_FINE represents fine position (bit inside coarse-position-pointed chunk) in graphic mode.
 .def POS_COLUMN = r21
 .def POS_ROWP = r20
@@ -87,21 +87,7 @@ main:
 		cpi r26, 0b11000000
 		brne load_mem_loop	; if not 0, repeat h_picture_loop
 
-	; test draw character routine
+	
-	call cursor_pos_home
-	ldi r19, 14
-	dctest:
-		ldi r18, 0x21
-		draw_chars:
-			mov HIGH_ACCUM, r18
-			call draw_char
-			inc r18
-			cpi r18, 0x7E
-			brne draw_chars
-		dec r19
-		brne dctest
-
-
 
 	; *** timer setup (use 16-bit counter TC1) ***
 	; The Power Reduction TC1 and TC3 bits in the Power Reduction Registers (PRR0.PRTIM1 and
@@ -121,6 +107,39 @@ main:
 	; Wait for data (it never exits)
 	; jmp comm_init
 
+
+
+	; test draw character routine
+	call cursor_pos_home
+	dctest:
+		ldi r18, 0x21
+		draw_chars:
+			mov HIGH_ACCUM, r18
+			call draw_char
+			inc r18
+			cpi r18, 0x7E
+			brne dc_continue
+			ldi r18, 0x21
+			dc_continue:
+			; wait
+			ser r19
+			dc_wait_loop_1:
+				ser r20
+				dc_wait_loop_2:
+					nop
+					nop
+					nop
+					nop
+					dec r20
+					brne dc_wait_loop_2
+				dec r19
+				brne dc_wait_loop_1
+			brne draw_chars
+		jmp dctest
+
+
+
+
 	forever:
 		jmp forever
 

pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm

@@ -4,7 +4,7 @@
 ; *******************************************
 
 ; Implemented following timings in http://blog.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/
-; Every line, for 52 times, it loads a byte from memory into PORTA register and then shifts the byte to the left to show another bit (do it 7 times)
+; Every line, for 46 times, it loads a byte from memory into PORTA register and then shifts the byte to the left to show another bit (do it 7 times)
 ; This also displays byte's MSB pixel "for free", as the video pin is PD7 (last bit of PORTA).
 
 ; This module generates a Composite PAL monochrome signal with a resolution
@@ -153,16 +153,13 @@ draw_picture:
 	push XH
 	push XL
 
-	; set X register to framebuffer start 0x0100
+	; set X register to framebuffer start
-	; (set it a byte before, because it will be incremented at first)
+	ldi r27, high(FRAMEBUFFER)
-	clr r27
+	ldi r26, low(FRAMEBUFFER)
-	ldi r26, 0xFF
 
 	; start 304 picture lines
 	ldi LINE_COUNTER, 256	; line counter
 	h_picture_loop:
-		; ***************** DRAW FIRST LINE *********************
-
 		; **** start line sync: 4uS, 96 cycles @ 24Mhz
 		; video pin goes low before sync
 		clr VG_HIGH_ACCUM										; 1 cycle