veswiki - Recent changes [en]

Main Page

E5frog — Sun, 21 Jun 2026 13:01:13 GMT

‎Snippets

Snippet:Blit

E5frog — Sun, 21 Jun 2026 12:57:33 GMT

Main Page

E5frog — Sun, 21 Jun 2026 12:55:20 GMT

‎Channel F Information

DASM

E5frog — Sun, 21 Jun 2026 12:53:08 GMT

File:Dasm-2.20.14.1-win-x64.zip

E5frog — Sun, 21 Jun 2026 12:51:04 GMT

E5frog uploaded File:Dasm-2.20.14.1-win-x64.zip

New page

Snippet:Blit

E5frog — Sun, 21 Jun 2026 12:38:11 GMT

Opcode

E5frog — Fri, 19 Jun 2026 23:54:45 GMT

@@ Line 29: / Line 29: @@
 == Snippets ==
-* [[Snippet:Blit|Blit subroutine]]
+* [[Snippet:Blit|Draw in two colors]]
-* [[Snippet:Multiblit|Multiblit subroutine]]
+* [[Snippet:Multiblit|Draw in all colors]]
-* [[Snippet:Plot|Plot subroutine]]
+* [[Snippet:Plot|Draw just one dot]]
-* [[Snippet:Playsong|Playsong subroutine]]
+* [[Snippet:Score|Keep track of score]]
-* [[Snippet:Score|Score subroutine]]
+* [[Snippet:Playsong|Make sweet monophonic music]]
 ** [[Snippet:Music_60.h|Music_60.h]]
 * [[Snippet:Pseudorandom numbers|Pseudorandom numbers]]

@@ Line 6: / Line 6: @@
 Code works with the '''DASM''' compiler.
 <pre>
 ;===========;

@@ Line 17: / Line 17: @@
 '''Programming:'''
 * [[Opcode]]s
-* [[Accessing VRAM]]
+* [[DASM|DASM compiler]]
 * [[Reading Controllers|Reading Controller and Buttons]]
 * [[Outputting Sound]]

@@ Line 16: / Line 16: @@
 <br>
 <br>
-Local copy:<br>
+Local copies:<br>
-[https://channelf.se/veswiki/images/4/40/Dasm-2.20.11.7z DASM 2.20.11 (.7z, 116kB)]
+[https://channelf.se/veswiki/images/4/40/Dasm-2.20.11.7z DASM 2.20.11 (.7z, 116kB)]<br>

@@ Line 1: / Line 1: @@
-The '''blit''' subroutine reads a two-color (1 bit per pixel) block of graphics data from ROM and displays it on the screen, using several parameters. It works much in the same way as the drawchar routine except for arbitrarily sized data. The code was originally taken from [[Disassembly:Videocart_26|Videocart 26]] and adapted to be more flexible and reusable.
+The '''blit''' subroutine reads a two-color (1 bit per pixel) block of graphics data from ROM and displays it on the screen, using several parameters. It works much in the same way as the BIOS drawchar routine except for arbitrarily sized data. The code was originally taken from [[Disassembly:Videocart_26|Videocart 26]] and adapted to be more flexible and reusable.
 The routine is separated into two parts, '''blitGraphic''' and '''blit'''. '''blit''' takes parameters in registers r1-r6, and retrieves graphics data from the location DC0 points to. It can be called independently of '''blitGraphic'''. '''blitGraphic''' takes hard-coded parameters from ROM at the address pointed at by DC0 and then calls the '''blit''' routine. When the parameters do not need to be dynamic, storing the parameters in ROM and calling the '''blitGraphic''' routine directly can be more efficient than writing them to the registers and calling '''blit'''.
 <pre>
 ;===========;
@@ Line 28: / Line 31: @@
 	; load the graphics address
 	lm
-	lr	Qu, A						; into Q
+	lr	QU, A						; storea data address in Q, one byte at the time
 	lm
-	lr	Ql, A
+	lr	QL, A
-	lr	DC, Q						; load it into the DC
+	lr	DC, Q						; copy Q into DC0
-	; call the blit function
+	; continue with the blit function
 ;---------------;
@@ Line 48: / Line 50: @@
 ; register reference:
 ; -------------------
-; r1 = color 1 (off)
+; r1 = color 0 (off) (alias: clear/bkg/blue/red/green)
-; r2 = color 2 (on)
+; r2 = color 1 (on)  (alias: clear/bkg/blue/red/green)
 ; r3 = x position
 ; r4 = y position
@@ Line 62: / Line 64: @@
 blit:
 	lis	1
 	lr	9, A						; load #1 into r9 so it'll be reset when we start
@@ Line 116: / Line 109: @@
 	outs	1						; output A in p1 (color)
-.blitTransferData:
+blit.transferData:
-	; transfer the pixel data
+	lis	6						; transfer the pixel data
-	li	$60
+	sl	4
 	outs	0
-	li	$c0
+	sl	1
 	outs	0
-	; and delay a little bit
-.blitSavePixelDelay:
+	lis	4
-	ai	$60						; add 96
+blit.savePixelDelay:
-	bnz	.blitSavePixelDelay				; loop if not 0 (small delay)
+	ai	$ff
 .blitCheckColumn:
@@ Line 143: / Line 138: @@
 	; return from the subroutine
 	pop
 </pre>
 To call the above functions, you should use:
@@ Line 154: / Line 149: @@
 </pre>
-for '''blitGraphic''', and:
+for '''blitGraphic''', and
 <pre>
-	; parameters have been loaded into r1-r6 beforehand
+	; when parameters have been loaded into r1-r6 beforehand
 	dci	graphic.data		; address of graphic data
 	pi	blit
@@ Line 166: / Line 161: @@
 <pre>
 graphic.parameters:
-	.byte	bkg			; color 1
+	.byte	bkg			; color 0
-	.byte	blue			; color 2
+	.byte	blue			; color 1
 	.byte	4			; x position
 	.byte	18			; y position

@@ Line 22: / Line 22: @@
 |-
 | '''W''' || [[Status register]] (x,x,x,ICB,O,Z,C,S) Exhange only via<br>the '''J''' register (R9)
 |-
 | '''ISAR''' || [[ISAR|Indirect Scratchpad Address Register]]
 |-
-| '''r''' || Scratchpad addressing as:
+| '''r''' || Scratchpad addressing ONLY as:
 {| border="1" cellspacing="1" cellpadding="4"
-| '''0 to 11''' || Select registers r0-r11
+| '''0 to 11''' || ISAR registers r0-r11
 |-
-| '''12''', '''S''' or '''IS''' || Reg. selected by ISAR <br> '''You can't call r12 (KU) using register number'''
+| '''S''' not preferred: '''(IS)''' || Reg. selected by ISAR <br> '''You can't call r12 (KU) using register number'''
 |-
-| '''13''', '''I''' or '''(IS)+''' || Reg. selected by ISAR, then ISAR = ISAR + 1 <br> '''You can't call r13 (KL) using register number'''
+| '''I''' not preferred: '''(IS)+''' || Reg. selected by ISAR, then (ISAR)++ <br> '''You can't call r13 (KL) using register number'''
 |-
-| '''14''', '''D''' or '''(IS)-'''  || Reg. selected by ISAR, then ISAR = ISAR - 1 <br> '''You can't call r14 (QU) using register number'''
+| '''D''' not preferred: '''(IS)-'''  || Reg. selected by ISAR, then (ISAR)-- <br> '''You can't call r14 (QU) using register number'''
 |}
 |-
@@ Line 86: / Line 90: @@
 ! style="width: 1.5em; cursor: help" title="Signed" | S
 |-
-| LR A, KU || 1 || 1 || A &larr; (KU)[r12] || %00000000 || $00 ||- ||- ||- ||- || S || 0
+| LR A, KU || 1 || 1 || A &larr; (KU) || %00000000 || $00 ||- ||- ||- ||- || S || 0
 |-
-| LR A, KL || 1 || 1 || A &larr; (KL)[r13] || %00000001 || $01 ||- ||- ||- ||- || S || 0
+| LR A, KL || 1 || 1 || A &larr; (KL) || %00000001 || $01 ||- ||- ||- ||- || S || 0
 |- =
-| LR A, QU || 1 || 1 || A &larr; (QU)[r14]|| %00000010 || $02 ||- ||- ||- ||- || S || 0
+| LR A, QU || 1 || 1 || A &larr; (QU) || %00000010 || $02 ||- ||- ||- ||- || S || 0
 |-
-| LR A, QL || 1 || 1 || A &larr; (QL)[r15]|| %00000011 || $03 ||- ||- ||- ||- || S || 0
+| LR A, QL || 1 || 1 || A &larr; (QL) || %00000011 || $03 ||- ||- ||- ||- || S || 0
 |-
-| LR KU, A || 1 || 1 || [r12]KU &larr; (A) || %00000100 || $04 ||- ||- ||- ||- || S || 0
+| LR KU, A || 1 || 1 || KU &larr; (A) || %00000100 || $04 ||- ||- ||- ||- || S || 0
 |-
-| LR KL, A || 1 || 1 || [r13]KL &larr; (A) || %00000101 || $05 ||- ||- ||- ||- || S || 0
+| LR KL, A || 1 || 1 || KL &larr; (A) || %00000101 || $05 ||- ||- ||- ||- || S || 0
 |-
-| LR QU, A || 1 || 1 || [r14]QU &larr; (A) || %00000110 || $06 ||- ||- ||- ||- || S || 0
+| LR QU, A || 1 || 1 || QU &larr; (A) || %00000110 || $06 ||- ||- ||- ||- || S || 0
 |-
-| LR QL, A || 1 || 1 || [r15]QL &larr; (A) || %00000111 || $07 ||- ||- ||- ||- || S || 0
+| LR QL, A || 1 || 1 || QL &larr; (A) || %00000111 || $07 ||- ||- ||- ||- || S || 0
 |-
-| LR K, P || 1 || 4 || [r12]KU &larr; (PC1U)<br>[r13]KL &larr; (PC1L) || %00001000 || $08 ||- ||- ||- ||- || L <br> L <br> S || 7 <br> B <br> 0
+| LR K, P || 1 || 4 || KU &larr; (PC1U)<br>KL &larr; (PC1L) || %00001000 || $08 ||- ||- ||- ||- || L <br> L <br> S || 7 <br> B <br> 0
 |-
-| LR P, K || 1 || 4 || PC1U &larr; (KU)[r12] <br>PC1L &larr; (KL)[r13] || %00001001 || $09 ||- ||- ||- ||- || L <br> L <br> S || 15 <br> 18 <br> 0
+| LR P, K || 1 || 4 || PC1U &larr; (KU) <br>PC1L &larr; (KL) || %00001001 || $09 ||- ||- ||- ||- || L <br> L <br> S || 15 <br> 18 <br> 0
 |-
 | LR A, IS || 1 || 1 || A &larr; (ISAR) || %00001010 || $0A ||- ||- ||- ||- || S || 0
@@ Line 110: / Line 114: @@
 | LR IS, A || 1 || 1 || ISAR &larr; (A) || %00001011 || $0B ||- ||- ||- ||- || S || 0
 |-
-| PK || 1 || 2.5 || PC1 &larr; (PC0)<br>PC0L &larr; (KL)[r13]<br>PC0U &larr; (KU)[r12] || %00001100 || $0C ||- ||- ||- ||- || L <br> L <br> S || 12 <br> 14 <br> 0
+| PK || 1 || 2.5 || PC1 &larr; (PC0)<br>PC0L &larr; (KL)<br>PC0U &larr; (KU) || %00001100 || $0C ||- ||- ||- ||- || L <br> L <br> S || 12 <br> 14 <br> 0
 |-
-| LR P0, Q || 1 || 4 || PC0L &larr; (QL)[r15]<br>PC0U &larr; (QU)[r14] || %00001101 || $0D ||- ||- ||- ||- || L <br> L <br> S || 17 <br> 14 <br> 0
+| LR P0, Q || 1 || 4 || PC0L &larr; (QL)<br>PC0U &larr; (QU) || %00001101 || $0D ||- ||- ||- ||- || L <br> L <br> S || 17 <br> 14 <br> 0
 |-
-| LR Q, DC || 1 || 4 || [r14]QU &larr; (DC0U)<br>[r15]QL &larr; (DC0L) || %00001110 || $0E ||- ||- ||- ||- || L <br> L <br> S || 6 <br> 9 <br> 0
+| LR Q, DC || 1 || 4 || QU &larr; (DC0U)<br>QL &larr; (DC0L) || %00001110 || $0E ||- ||- ||- ||- || L <br> L <br> S || 6 <br> 9 <br> 0
 |-
-| LR DC, Q || 1 || 4 || DC0U &larr; (QU)[r14]<br>DC0L &larr; (QL)[r15] || %00001111 || $0F ||- ||- ||- ||- || L <br> L <br> S || 16 <br> 19 <br> 0
+| LR DC, Q || 1 || 4 || DC0U &larr; (QU)<br>DC0L &larr; (QL) || %00001111 || $0F ||- ||- ||- ||- || L <br> L <br> S || 16 <br> 19 <br> 0
 |-
-| LR DC, H || 1 || 4 || DC0U &larr; (R10)<br>DC0L &larr; (R11) || %00010000 || $10 ||- ||- ||- ||- || L <br> L <br> S || 16 <br> 19 <br> 0
+| LR DC, H || 1 || 4 || DC0U &larr; (HU)<br>DC0L &larr; (HL) || %00010000 || $10 ||- ||- ||- ||- || L <br> L <br> S || 16 <br> 19 <br> 0
 |-
-| LR H, DC || 1 || 4 || R10 &larr; (DC0U)<br>R11 &larr; (DC0L) || %00010001 || $11 ||- ||- ||- ||- || L <br> L <br> S || 6 <br> 9 <br> 0
+| LR H, DC || 1 || 4 || HU &larr; (DC0U)<br>HL &larr; (DC0L) || %00010001 || $11 ||- ||- ||- ||- || L <br> L <br> S || 6 <br> 9 <br> 0
 |-
 | SR 1 || 1 || 1 || Shift (A) right one bit, fill with %0 || %00010010 || $12 || 0 || X || 0 || 1 || S || 0
@@ Line 168: / Line 172: @@
 | PI mn|| 3 || 6.5 || A &larr; m<br>PC1 &larr; (PC0)+1<br>PC0L &larr; n<br>PC0U &larr; (A)<br>[A is destroyed] || %00101000 %xxxxxxxx %xxxxxxxx || $28 $xx $xx ||- ||- ||- ||- || L <br> S <br> L <br> L <br> S || 3 <br> D <br> C <br> 14 <br> 0
 |-
-| JMP mn || 3 || 5.5 || A &larr; m<br>PC0L &larr; n<br>PC0U &larr; (A)<br>[A is destroyed] || %00101001 %xxxxxxxx %xxxxxxxx || $29 $xx $xx ||- ||- ||- ||- || L <br> L <br> L <br> S || 3 <br> c <br> 14 <br> 0
+| JMP mn || 3 || 5.5 || A &larr; m<br>PC0L &larr; n<br>PC0U &larr; (A)<br>[A now contains m] || %00101001 %xxxxxxxx %xxxxxxxx || $29 $xx $xx ||- ||- ||- ||- || L <br> L <br> L <br> S || 3 <br> c <br> 14 <br> 0
 |-
 | DCI mn || 3 || 6 || DC0U &larr; m<br>PC0+1<br>DC0L &larr; n<br>PC0+1 || %00101010 %xxxxxxxx %xxxxxxxx || $2A $xx $xx ||- ||- ||- ||- || L <br> S <br> L <br> S <br> S || 11 <br> 3 <br> E <br> 3 <br> 0
@@ Line 221: / Line 225: @@
 | ADC || 1 || 2.5 || DC0 &larr; (DC0)+(A) || %10001110 || $8E ||- ||- ||- ||- || L <br> S || A <br> 0
 |-
-| BR7 n || 2 || 2 (no branch)<br>2.5 (branch) || if ISARL != 7: PC0 &larr; (PC0) + n +1 || %10001111 %xxxxxxxx || $8F $xx ||- ||- ||- ||- || S <br> S <br> L <br> S || 3 <br> 0 <br> 1 <br> 0
+| BR7 n || 2 || 2 (no branch)<br>2.5 (branch) || if (ISAR & 7)!=7: PC0 &larr; (PC0) + n +1 || %10001111 %xxxxxxxx || $8F $xx ||- ||- ||- ||- || S <br> S <br> L <br> S || 3 <br> 0 <br> 1 <br> 0
 |-
 | BR n || 2 || 3.5 || PC0 &larr; (PC0)+n+1 || %10010000 %xxxxxxxx || $90 $xx ||- ||- ||- ||-  ||  ||
@@ Line 247: / Line 251: @@
 | NS r || 1 || 1 || A &larr; (A)AND(r) || %1111xxxx || $Fx ||0 ||X ||0 ||X || S || 0
 |-
-|  || IRQ || 5.5 || PC0L &larr; Int address(l)<br>PC0U &larr; Int.Address(u)<br>PC1<-PC0 ||  ||  ||- ||- ||- ||- || L <br> L <br> L <br> S || 1C <br> 0F <br> 13 <br> 0
+|  || Hardware event: IRQ || 5.5 || PC0L &larr; Int address(l)<br>PC0U &larr; Int.Address(u)<br>PC1<-PC0 ||  ||  ||- ||- ||- ||- || L <br> L <br> L <br> S || 1C <br> 0F <br> 13 <br> 0
 |-
-|  || RESET || 3.5 || PC0 &larr; 0<br>PC1 &larr; PC0 || || ||- ||- ||- ||- || S <br> L <br> S || 1C <br> 8 <br> 0
+|  || Hardware event: RESET || 3.5 || PC0 &larr; 0<br>PC1 &larr; PC0 || || ||- ||- ||- ||- || S <br> L <br> S || 1C <br> 8 <br> 0
 |}