Create animated displays for MSX screen 2 images.


Project details
  The Screen 2 Show project involves both MSX and PC computers. At the MSX side, aims at developing display algorithms in Assembly. At the PC side, aims at developing tools to help on adding the display code to images converted to MSX.
  Currently, this project works only with MSX 1 screen 2 format. Thus, it is extensible to other screen formats.


  How the program works

      Arquivo                     RAM                  VRAM

 10 SCREEN 2                9000 | MPPPP  |      0000 | PPPPPP |
 20 BLOAD"TELA.SCR",R  ->   .... | CCCCD  |  ->  .... |        |
 30 GOTO 30                 FFFF |        |      2000 | CCCCCC |

  The first action is to load the program into the RAM, starting at the address &H9000. It is divided into:

• The main program (marked as a green "M")
• The compacted image (marked as a blue "P" for the pattern image and a red "C" for the color image)
• The display program (marked as cyan "D")

  Different from the previous version, which used compacted images, the main program now only calls the display routine that copies image from RAM address &H9000 to VRAM.


  File layout

Part	MSX Address
Header	8FF5
Main code	8FFC
Image pattern	9000
Image color	A800
Display code	C000

  Header description

MSX Address	Value	Description
-	FE	MSX Binary file ID
-	F5	Program beggining
-	8F	Program beggining (8FF5)
-	xx	End of File
-	xx	End of file
-	FC	Exec beggining
-	8F	Exec beggining (8FFC)
8FF5	xx	Type of display:  00 - Direct  01 - Top to bottom  02 - Left to right  03 - Diagonal  04 - Snail in  05 - Frame
8FF6	4D	"M"
8FF7	61	"a"
8FF8	72	"r"
8FF9	4D	"M"
8FFA	53	"S"
8FFB	58	"X"

  - → Not used address.
  xx → Undefined value.


  Main code

 line code              mnemonics
------------------------------------------------------------------------
   10 			ORG  &H8FFC
   20 CD 00 C0		CALL &HC000		; Calls display routine
   30 C9		RET			; end

  Display codes

  10		ORG &HC000
  20 TELA:	LD   BC,&H1800		; $
  30 		LD   DE,0		; $
  40 		LD   HL,&H4000		; $
  50 		CALL &H5C		; $ Particular routine to display screen
  60 		LD   BC,&H1800		; $ In this case, copies direct
  70 		LD   DE,&H2000		; $
  80 		LD   HL,&H5800		; $
  90 		CALL &H5C		; $
  100		RET 			; $

  Access here:

  Former project that compressed screen
  Display codes
  Support: Screen 2 Achitecture