sound_effect bug

[johanberntsson]

@sound_effect 0 3 doesn't stop the current sound. Ozmoo seems to need the actual id of the sound to stop it. 0 is normally the last/current sound. I don't think that's documented in the Z-Machine standards, but it is noted in Infocom's sound.spec for the Amiga, and works in all the other terps.

[KVonGit]

Hello, I came here to create this same issue, and to mention the volume when using the XMEGA65 emulator. I am not sure the volume is an actual issue when using a real machine, though...

The MEGA65 versions of The Lurking Horror and Sherlock both play sounds at 25% volume on the xemu MEGA65 emulator, compared to playing the "standard" versions of them any other way on this same Windows 11 machine (be it Frotz, DOSBox, WinUAE, etc.). I also created test games with my own sounds, and the results were the same. I also ran PLAY "CEGCEGCEG" from the main shell in the XMEGA65, and that plays at normal volume levels.

After a 6502 assembly language crash-course (which was actually quite fun), I ended up finding that removing the code which converts the value from a range of 0..255 to a range of 0..64 fixes the low volume issue for me in the emulator (on Windows 11 and Arch Linux).

; sound.asm, line 777
+    ; MEGA65's volume is [0,64]. Convert from z-machine [0,255]
     ; Commented out the next 4 lines for the XMEGA65 - KV
    ;clc
    ;ror
    ;clc
    ;ror

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I admittedly know very little about any of this, and I am learning as I go. So, all apologies if Ozmoo simply has to convert this value for actual machines.

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Thanks for Ozmoo and PunyInform, by the way!

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EDIT

The volume issue seems to be something to do with my Windows 11 machine, or the XMEGA65 build on that machine. So, forget I mentioned this. The volume is fine when I try it with the XMEGA65 I had to build from source to install on Arch Linux.