How to play CD audio tracks on SCD + some advices

[blabla]

It seems like some programmers out of there still don't know how to play CD tracks but in fact it's very easy !

cdplay2 2 'Plays the first track , cdplay2 loops it
'to unloop the song , simply use cdplay instead
print "NEVER GONNA GIVE YOU UP"
do

loop


You can stop playing a track using CDSTOP.
You can pause a track with CDPAUSE and unpause it with CDUNPAUSE.
See ? I told you that was going to be easy !

Download the example

If you want to make a game for Sega CD then this is almost a requirement , you will quickly run out of space if you don't do this.
Basiegaxorz stores the whole game in the WRAM (Word-Ram) which is 256kb long.
However , Red book audio tracks doesn't use the memory nor the cpu plus they sound a lot better than FM tracks.
There is another way to load your tiles using addscd/loadscd.
That will be needed if your project is big because that means the tiles will no longer be stored in the WRAM.
loadscd_data.bex (provided with Basiegaxorz) is a good example of this if you want more details.

And before you compile it , don't forget to check "Compile as a BOOT iso file for Sega CD".

"Compile as a Sega CD program" gives you a .scd file.

[Deleted]

Thanks for the CD audio example!

Do you understand enough to explain loading data from CD? Say, loading some numbers from CD into an array?

[blabla]

Sept 9, 2013 15:49:23 GMT -5 @theloon said:

Thanks for the CD audio example!

Do you understand enough to explain loading data from CD? Say, loading some numbers from CD into an array?

You can easily load tiles & Sega CD programs (*.scd) from CD using loadscd.
Here's an exemple that shows how i load & draw a picture from the CD :

addscd happysonic_picture1.bin 'Cluster 2

'The Cluster 0 & 1 are already used so the background will use the 2nd Cluster.
'I converted the picture using ImaGenesis 4000 Beta

drawtilesinc 128,0,0,40,28 'Draws a 320x224 picture from the 128th tile
loadscd 2,VRAM,0,1120,128 'Loads from CD the background made of 1120 tiles and put all the loaded tiles from the 128th tile
pallettes pallette1,0,0,16 'The palette is not loaded from CD
'When you convert an image using ImaGenesis 4000 Beta , the software
'also gives you a palette for the converted image

do

loop

Loadscd here works a bit like loadtiles. I think its looks cleaner and better than loading tiles using loadtiles & datafile.
It's one of the reasons why i would rather make my games for Sega CD than for Sega Genesis. It seems less glitchy too...

If you want to load Array or variables... Well too bad , you cannot do that !
You can load arrays but there are no way to create data from them. According to the doc :

This command loads data from a cluster on the CD, and then stores it into a variable, or an array. <Start Position> specifies the location within the cluster in which LOADSCD will load data into the variable. The number of bytes that are read are pre-determined by the compiler (based on the actual size of the variable or array). Putting data into the right places, and then creating an address to retrieve them is tricky. More than likely, you'll probably use a hex editor to create your data. I'll try to make a utility later that will generate clusters based on a script or something.

However , Arrays aren't the largest things on earth and in fact i don't use them at all.

You can still load Sega CD Programs !
I'm providing you a very basic example here :
goo.gl/ZuXOHV
Note that if you want to load CD data when you're playing a scd file , the clusters are still same as the iso boot so you must add all the resources for all games in the boot.
To compile the example , compile Program2.bex as a Sega CD program. Take the basic.scd file in basiegaxorz folder , rename it game_2.scd and put it in the LoadSCD_ex folder.
Then compile Main_BOOT.bex as a BOOT iso file.

This can be also useful for compilations. (Recommended for BEX Megadrive games which are less than 256kb)
For example I can put Crazy Cars , Sonic Arena ,
Tower Tic Tac Toe and CrazyBus all in one disc !
Sounds cool , huh ?
Basiegaxorz is provided with a good example for CD compilations called play_games.bex.
Basically all you need to do is to compile each game as a Sega CD program and then compile the main program as a boot iso file.

Hope that'll be useful for ya !

[Deleted]

Sounds like you can load data into an array but you need to know the exact cluster on the CD. I was hoping to load levels from CD.

Does memory get wiped when you switch from game_1.scd to game_2.scd? Maybe I could store game levels on separate "games".

[blabla]

Sept 10, 2013 8:54:07 GMT -5 @theloon said:

Does memory get wiped when you switch from game_1.scd to game_2.scd? Maybe I could store game levels on separate "games".

Yup , all the memory is cleared when you load Sega CD Program and yes it is possible to seperate your levels like this.

[assortedkingdede]

Sept 9, 2013 17:29:37 GMT -5 blabla said:

Sept 9, 2013 15:49:23 GMT -5 @theloon said:

Thanks for the CD audio example!

Do you understand enough to explain loading data from CD? Say, loading some numbers from CD into an array?

You can easily load tiles & Sega CD programs (*.scd) from CD using loadscd.
Here's an exemple that shows how i load & draw a picture from the CD :

addscd happysonic_picture1.bin 'Cluster 2

'The Cluster 0 & 1 are already used so the background will use the 2nd Cluster.
'I converted the picture using ImaGenesis 4000 Beta

drawtilesinc 128,0,0,40,28 'Draws a 320x224 picture from the 128th tile
loadscd 2,VRAM,0,1120,128 'Loads from CD the background made of 1120 tiles and put all the loaded tiles from the 128th tile
pallettes pallette1,0,0,16 'The palette is not loaded from CD
'When you convert an image using ImaGenesis 4000 Beta , the software
'also gives you a palette for the converted image

do

loop

Loadscd here works a bit like loadtiles. I think its looks cleaner and better than loading tiles using loadtiles & datafile.
It's one of the reasons why i would rather make my games for Sega CD than for Sega Genesis. It seems less glitchy too...

If you want to load Array or variables... Well too bad , you cannot do that !
You can load arrays but there are no way to create data from them. According to the doc :

This command loads data from a cluster on the CD, and then stores it into a variable, or an array. <Start Position> specifies the location within the cluster in which LOADSCD will load data into the variable. The number of bytes that are read are pre-determined by the compiler (based on the actual size of the variable or array). Putting data into the right places, and then creating an address to retrieve them is tricky. More than likely, you'll probably use a hex editor to create your data. I'll try to make a utility later that will generate clusters based on a script or something.

However , Arrays aren't the largest things on earth and in fact i don't use them at all.

You can still load Sega CD Programs !
I'm providing you a very basic example here :
goo.gl/ZuXOHV
Note that if you want to load CD data when you're playing a scd file , the clusters are still same as the iso boot so you must add all the resources for all games in the boot.
To compile the example , compile Program2.bex as a Sega CD program. Take the basic.scd file in basiegaxorz folder , rename it game_2.scd and put it in the LoadSCD_ex folder.
Then compile Main_BOOT.bex as a BOOT iso file.

This can be also useful for compilations. (Recommended for BEX Megadrive games which are less than 256kb)
For example I can put Crazy Cars , Sonic Arena ,
Tower Tic Tac Toe and CrazyBus all in one disc !
Sounds cool , huh ?
Basiegaxorz is provided with a good example for CD compilations called play_games.bex.
Basically all you need to do is to compile each game as a Sega CD program and then compile the main program as a boot iso file.

Hope that'll be useful for ya !

I would like to ask if there is way to load the data in increments because I am working on an FMV demo but 7 frames will completely fill up word ram so I thought that I could load 5 frames and then clear the first frame as I load the next from an scd file,  any advice would help.
Thanks!