Text from Ice Cream Castle
| Description: | Almond |
| Text: | HI .... AYAACODA ? TODAY I WILL TALK A BIT ABOUT CODING AND SO ON.... SOME TIME AGO I SAW AND PART IN A MSI DEMO . IT CONTAINS VERTICAL RASTER (4 BITS BIG) WHICH WERE MADE WITH AN ILLEGAL OPCODE ($72) . SO I THOUGHT ABOUT AN OPCODE THAT WORKS A BIT FASTER THAN 1/2 CYCLE . . SO I FOUND ANOTHER OPCODE ($2H) .. IT WORKS IN A 1/4 CYCLE (2 BITS) .. THE CRB(00,X) $XXXX CODE WRITES COLORS FROM $00,X TO $XXXX . . SO YOU CAN MAKE VERTICAL SPLITS !!! . BUT YOU CAN NOT CHANGE THE COLORS HORIZONTAL CAUSE THAN CRASHES THE TIMING ..ANOTHER PROBLEM IS $D012 . THIS CODE ($2H) WORKS ONLY BETWEEN $36 AND $ED ($D012) . . THAT IS WHY YOU CAN NOT SET THE SPLITS IN THE UPPER OR LOWER BORDER . .A FURTHER FACT IS , THAT THE $XXXX ADRESS WORKS ONLY BETWEEN $D021 AND $D037 . THAT MEANS NO SIDE - BORDER SPLITS . EVEN IF YOU USE $D016 TO OPEN THE SIDEBORDER (DESTROY $D020) , THAN THE 4TH BIT OF $D016 HAS INFLUENCE ON THE CRB(00,X) $XXXX CODE AND THE SCREEN ($D011) WILL SWITCHED OFF . FOR ALL OF YOU , WHO THINK NOW ABOUT CHANGING $D021 IN $D025,$D026 OR ANOTHER SPRITE COLOR ADRESS , I MUST SAY SORRY . CAUSE EVERY SPRITE WHICH IS ON THE SCREEN MOVES THE BEGINNING OF X-START POINT OF THE VIC 10 CHARS TO THE RIGHT . YOU ALSO HAVE TO AVOID CHARS ON THE SCREEN CAUSE THE SPLIT CAN NOT MOVE THROUGH CHAR PIXELS , SO SET THE 9TH BIT OF $D018 ON $02 AND CLEAR ALL THE CHAR MEMORY !!! ALSO BE SURE THAT $D051 STANDS ALWAYS ON $00 . THAT WILL PREVENT TIMING AND COLOR BUGS . SO I HOPE YOU HAVE UNDERSTUDDEN ALL , IF NOT , READ AGAIN ......... BY THE WAY , YOU CAN STOP THE MOVEMENT WITH JOY BUTTON IN PORT 2 !!! |
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