New community dev tool uploaded: Simplest Sound Effects Library for BASIC programs

[DusanStrakl 102]

Simplest Sound Effects Library for BASIC programs

View File

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Usage

Because of its simplicity the library can be stored in a 1K space below basic programs, starting at $0400.

Save the EFFECTS.PRG program in the directory where your BASIC program is stored, which would typically be in the same directory from where you are running the emulator.

 

Load library with LOAD command:

 

LOAD”EFFECTS.PRG”,8,1,$0400

 

Since this routine after the first run adds a new interrupt handler it is good practice to only load it once. It is therefore recommended to do a simple check:

 

IF PEEK($400)=0 THEN LOAD”EFFECTS.PRG”,8,1,$0400

 

 

And that is it. Now you only need to call the needed sound effect from the BASIC program with a simple SYS command. We have four different effects so four different addresses can be called:

 

SYS $400	PING	Is designed for events like picking coins or rewards.
SYS $403	SHOOT	Effect that can be used for shooting the gun or other weapon.
SYS $406	ZAP	Electricity zapping or perhaps a laser gun sound.
SYS $409	EXPLODE	Long explosion for when we successfully blow something up

 

Alternative binary named EFFECTSHI.PRG that loads into memory at $9000 can be downloaded. Of course calls are then $9000 for PING, $9003 for SHOOT, $9006 for ZAP and $9009 for EXPLODE.

 

Full source code and walk through is available at my blog:

https://www.8bitcoding.com/p/simplest-sound-effects-library-for.html

 

Demo video:

 

 

 

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• Submitter
  DusanStrakl
• Submitted
  08/12/20
• Category
  Dev Tools

 

Edited September 25, 2020 by DusanStrakl

[AndyMt 162]

Thanks a lot for this! The interrupt handler is particularly valuable for me and also your blog post explaining how it works. I managed to adapt the code slightly and use it in my upcoming "Invaderz" game (written in C)  - if that's ok?.

I'm just thinking to improve it further so it would use multiple PSG channels. I have the situation that sound effects could overlap (shots + explosions). That would require the player to use a new channel every time a previous effect is still running - let's say for up to 4 channels. Right now I just hacked this by duplicating the code and the variables 4 times - with some checks which one to use in the beginning. Not the most elegant way of doing it. But my 6502 assembler skills are just not good enough (yet) for anything else (I used to code 68000 assembler, totally different).

Did you consider improving the player in that direction?

[DusanStrakl 102]

Of course Andy, that's why I posted the source code so that anybody can reuse it.

I didn't plan to make this particular library multichannel but it should be pretty easy doable. I think your approach to simply duplicate the code four times for four channels is totally fine, the other approach would be a loop.

I am actually working on another library that is intended to play music in the background and supports full ADSR sound modulation and would have few predefined instruments etc. It is almost working but I am currently distracted by another project but hopefully I can find few days to finish and test it.

[rje 232]

I'm going to plug this into my Rogue Forest program, because it's got exactly what I want: simple sound effects.

 

[DusanStrakl 102]

22 hours ago, rje said:

I'm going to plug this into my Rogue Forest program, because it's got exactly what I want: simple sound effects.

 

Great, I am glad you find it useful.

[BruceMcF 291]

That's really nice ... xForth uses $8000-$9BFF as seven block buffers, so the $9000 verdipon can be installed at the cost of one buffer.

Does it preserve registers? If so:

CODE PING $9000 CALL, ENDCODE

...and a PING word would be defined. Otherwise I'll have to add PHX, PHY, PLX, PLY, to my small set of code words.

(NB. Don't look for ;CODE and friends in the uploaded version, that's in the next on coming this weekend).

 

Edited August 29, 2020 by BruceMcF

[rje 232]

So I wrote this quick-and-dirty BASIC program just to play with the values, and it works ... as long as I don't try to change the envelope while the sound routine is actually running.  In other words, you have to wait for the decay to complete before changing a value!

 

TEST-SOUND.BAS

[DusanStrakl 102]

22 hours ago, BruceMcF said:

That's really nice ... xForth uses $8000-$9BFF as seven block buffers, so the $9000 verdipon can be installed at the cost of one buffer.

Does it preserve registers? If so:

CODE PING $9000 CALL, ENDCODE

...and a PING word would be defined. Otherwise I'll have to add PHX, PHY, PLX, PLY, to my small set of code words.

(NB. Don't look for ;CODE and friends in the uploaded version, that's in the next on coming this weekend).

 

Very cool! No I don't preserve registers.

[DusanStrakl 102]

16 hours ago, rje said:

So I wrote this quick-and-dirty BASIC program just to play with the values, and it works ... as long as I don't try to change the envelope while the sound routine is actually running.  In other words, you have to wait for the decay to complete before changing a value! 

 

TEST-SOUND.BAS 871 B · 0 downloads

Interesting. It might be tricky to poke values directly because BASIC might be too slow and the player is called 50 times per second. Maybe try stopping the current sound by poking 0 into "running" first, change the envelope parameters and then start the sound by poking 255 into "phase". Obviously I haven't tried this...

[rje 232]

On 8/30/2020 at 3:37 PM, DusanStrakl said:

Interesting. It might be tricky to poke values directly because BASIC might be too slow and the player is called 50 times per second. Maybe try stopping the current sound by poking 0 into "running" first, change the envelope parameters and then start the sound by poking 255 into "phase". Obviously I haven't tried this...

I'll add these and see what happens!  

stop:
;*******************************************************************************
        ldx #0
        stx running
        rts

restart:
;*******************************************************************************
        ldx #$ff
        stx phase
        rts
	

Edited August 31, 2020 by rje

[BruceMcF 291]

On 8/31/2020 at 4:26 AM, DusanStrakl said:

Very cool! No I don't preserve registers.

OK, I've added PUSH, and PULL, to "comma" ("copy data into the current spot in the dictionary") whichever register storage to the hardware stack is required by the implementation.

I've only recently downloaded the CX16 emulator, and I don't have sound, but I'm pretty sure it will be straightforward. I don't touch interrupts at all at this point in Forth compiler development.

[mobluse 14]

I tried both EFFECTS and EFFECTSHI with my program Aritm, but in both cases it deletes the screen and changes background color after the sound, and then you cannot see what you type. I use R38 of the emulator in most updated Windows 10.

I added these lines to Aritm:

Quote

10 IF PEEK($9000)=0 THEN LOAD"EFFECTSHI.PRG",8,1,$9000

3612 SYS $9000

Quote

10 IF PEEK($400)=0 THEN LOAD"EFFECTS.PRG",8,1,$0400

3612 SYS $400

 

Edited September 12, 2020 by mobluse

[DusanStrakl 102]

On 9/12/2020 at 7:15 AM, mobluse said:

I tried both EFFECTS and EFFECTSHI with my program Aritm, but in both cases it deletes the screen and changes background color after the sound, and then you cannot see what you type. I use R38 of the emulator in most updated Windows 10.

I added these lines to Aritm:

 

Thanks for the comment Mikael. It seems that there was some interference between effects library and some VERA related actions from BASIC programs, specifically in your case, scrolling of the screen. I added some code to save and restore VERA state inside the IRQ Player. I tried both EFFECTS.PRG and EFFECTSHI.PRG with your program and it seems to work without problems now. 

[mobluse 14]

22 hours ago, DusanStrakl said:

Thanks for the comment Mikael. It seems that there was some interference between effects library and some VERA related actions from BASIC programs, specifically in your case, scrolling of the screen. I added some code to save and restore VERA state inside the IRQ Player. I tried both EFFECTS.PRG and EFFECTSHI.PRG with your program and it seems to work without problems now. 

Yes, both EFFECTS and EFFECTSHI works for me in Aritm now. In order to use it with the "Try it now" button one would have to be able to upload disk images or have some way of including the sound effects library in a single file with my BASICv2-program. Edit: The "Try it now" button for Aritm with sound works now. I put both files in a zip-file and updated. It automatically selected the right file, but if it should choose wrong you can edit which file is the main program.

Edited September 25, 2020 by mobluse

[mobluse 14]

In the table EXPLODE and ZAP should switch places.

[DusanStrakl 102]

4 hours ago, mobluse said:

In the table EXPLODE and ZAP should switch places.

Thanks. Corrected.

[mobluse 14]

On 9/25/2020 at 9:43 PM, DusanStrakl said:

Thanks. Corrected.

Yes, it's fixed in the first post here, but the table is still wrong on the file download page: https://www.commanderx16.com/forum/index.php?/files/file/62-simplest-sound-effects-library-for-basic-programs/

[DusanStrakl 102]

5 minutes ago, mobluse said:

Yes, it's fixed in the first post here, but the table is still wrong on the file download page: https://www.commanderx16.com/forum/index.php?/files/file/62-simplest-sound-effects-library-for-basic-programs/

Darn it. Thanks, you have eagle eyes. I hope that is fixed now too.

[paulscottrobson 42]

Did you used to own an ORIC ?

[DusanStrakl 102]

4 hours ago, paulscottrobson said:

Did you used to own an ORIC ?

Ha, ha, yes I did. It was my first computer. Anybody who did will know these four sound effects  

[rje 232]

So I've been thinking about an API that wraps your code and makes it configurable via the X16's ABI pseudo-registers.

I haven't thought deeply enough about it, so it might be ridiculous/overkill, but here's what I'm thinking of doing:

• R1a. voice
  R1b. waveform
• R2 a + b. frequency (16 bits)
• R3a. pulse width
• R4a. channel
  R4b. volume
• (R5a. attack)
  R5b. decay
• (R6. sustain & release)

Then two API calls:

$9000 (or wherever): SSND - sets up and plays a voice, using all of the pseudo-registers above.

$9003 (or wherever): PLAY - plays a previously set-up voice, using the first three pseudo-registers.

Obviously it's not designed for playing music.  But maybe it would be useful for configuring the voices initially (generally useful for sound effects in other words).  I know you've addressed the music angle in your other library on your blog.

 

Presumably, the API calls would copy the register values into memory.  The voice, waveform, frequency, pulse width, channel, and volume would go into VERA. ADSR would take up 64 bytes (4 bytes per voice) in somewhere convenient in main RAM (maybe $200?).

 

Edited April 1 by rje

[ZeroByte 82]

Here's a demo of YM music I did in BASIC a while back.  STARDUST.PRG

The logic for the bass line is kind of convoluted - I just put all possible notes in different voices and just play the different notes in the progression on the different voices. That freed the music data up to be dead simple. It's raw OCT+KC register values ($28+voice#), or it's $FF which is a rest. There's something in the code about $FE but I didn't use it, and now I don't know what the point of those was.

The demo plays the "stardust" song from Lazy Jones (C64 game) - also known by sports fans as "Zombie Nation" or "that o O OH OHH OH!" song they play before kickoffs. Zombie Nation (a techno musician) made that version and called it something like kernelkraft9000...

If I were to re-think this for "general use" I would re-order the bytes written to the voices in the "load patches" subroutine to loop through the registers in order of YM address, and not group them by Operator - that way, a patch could be easily stored as 26 bytes to be written out to: $20, $38, $40, $48, $50, $58, $60, $68 .. etc ... $F0, $F8  (add channel number to each of these reg values to use the patch for whichver voice, so voice 4 would be $24, $3C, $44, $4C, etc)

I'm thinking about making an instrument browser in basic because I have a giant truckload of OPM instrument packs from SEGA games - I'd want to de-dup them and somehow name them in a sane fashion, but then have an X16 program that would just loop some simple sequences on a voice and let you select them one by one and listen to them. Deflemask --sux-- for browsing instruments, ESPECIALLY from VOPM files.

Edited April 2 by ZeroByte