Saturday, 23 May 2009

Last Amazon - Tape Mastering+Linking

Saturday 23rd May 2009

Weather is ever so nice today, but I had nothing to do, nowhere to go to meet people. So I decided to do some more of The Last Amazon trilogy project. This time something completely different. I took a look at the latest IRQ tape loader source code by Martin Piper and decided to alter it to make the loader slightly shorter and also base the loader on the same loader I used for Joe Gunn tape version.

I dug out the ACME cross assembler and first of all, I altered the loader's flashing border methods. Rather than have the classic cyber load colours, I wanted something much different. So I changed the Cyber load colours to something like this:

COLOURBASE: LDA #$06
STA $D020
LDA #$00
STA $D020

then I changed the INC $D020 where the check sum counts, to INC COLOURBASE+1 so that after each check sum, the loader will change the colour of the thin stripes per load.

Once I done this, I decided to make some additional features to the routine. Starting with altering the speed of the tape loader to medium/fast speed, because duplication can be a problem if the speed of the loader is too fast. Secondly I updated the scroll text routine, and removed the on screen messages "NOW LOADING LEGION OF THE DAMNED" to shorten the loader in size.

Also to shorten the size, I deleted the routines that saves and loads the loader's flashing sprite, and the counter routine. Both of those were not required for this TND/Psytronik loader. I linked the program files of the music, picture data and then game data and assembled the source to get a tape master.

Now I test the assembled tape master file and assembled it to a .prg file and run it in WinVice. I created a test .tap (or tape image as you would prefer to call it) and started to extract all the data on to the .tap image. I tested the loader, and it worked nicely. So I did the same mastering for different games. Then created a disk menu for the master.

The other job which I did was linked all the loader pics (With press space message) to each Last Amazon game. So I created my very own Picture Linker program, which will link pictures made with the Vidcom to TNDPic converter (Only for my personal use :o)). Then I inserted all the TNDPic files into the directory of my Picture Linker source. Then I added all the C64 files (Music, the games, etc) to the source. I assembled the source and linked the picture to each file successfully. Those featuring the linked pictures (With the press space message) will only be for the disk version.

This Last Amazon Trilogy project is nearly finished, all I need to do is program a special disk menu for the disk version of the game and then that's it :)

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