lynx Audio counters?

[StinkerB06]

According to Part 14 of the Atari Lynx Programming Tutorial, it says that Bit 3 in a "Static and dynamic control" register enables its timer.

 

As for audio timers, does clearing it make the channel stay active forever, or does it shut itself off?

I notice that Lynx Chipper cuts off the note after 2 seconds of playback, so it probably means the counter is on the max value and "Reload" (Bit 4) is disabled.

I know that an IRQ is generated when the value is reloaded, does it reset LFSR sound phase?? Does this also affect "Integrate" (Bit 5) mode?

Also, what does "Reset timer done" (Bit 6) do? Does it generate IRQ when it's changed to something different than last write?

Is "Enable interrupt" (Bit 7) persistent on audio? It is used as LFSR feedback bit 7, but in Chipper its checkbox is grayed out. Probably means feedback bit 7 can't be used while counting.

[+karri]

According to Part 14 of the Atari Lynx Programming Tutorial, it says that Bit 3 in a "Static and dynamic control" register enables its timer.

 

As for audio timers, does clearing it make the channel stay active forever, or does it shut itself off?

I notice that Lynx Chipper cuts off the note after 2 seconds of playback, so it probably means the counter is on the max value and "Reload" (Bit 4) is disabled.

I know that an IRQ is generated when the value is reloaded, does it reset LFSR sound phase?? Does this also affect "Integrate" (Bit 5) mode?

Also, what does "Reset timer done" (Bit 6) do? Does it generate IRQ when it's changed to something different than last write?

Is "Enable interrupt" (Bit 7) persistent on audio? It is used as LFSR feedback bit 7, but in Chipper its checkbox is grayed out. Probably means feedback bit 7 can't be used while counting.

 

The Bit 3 stops the audio when it is cleared.

 

Chipper has a alot of extra functionality. It may be easier to use the C-version of ABCmusic to experiment in what different bits are doing.

testaudio.zip

[sage]

The bit is in a different register. Using it, would requiere a lot of addidtional commands (mask out the bit, read, modify write register etc). not impossible but unnecessary.

[StinkerB06]

 

The Bit 3 stops the audio when it is cleared.

 

Chipper has a alot of extra functionality. It may be easier to use the C-version of ABCmusic to experiment in what different bits are doing.

What do I have to do with those files? I don't get it.

 

Can you provide me with a program that has an onscreen visual of every register, so that we can understand sound more better?

[+karri]

What do I have to do with those files? I don't get it.

 

Can you provide me with a program that has an onscreen visual of every register, so that we can understand sound more better?

 

Of course.

 

You can download a visual tool to access all the registers from http://www.ataritimes.com/index.php?ArticleIDX=418

 

I wrote this in 2004 and all the register bits are easily accessible from a graphical interface.

 

 

The top row contains the hardware bits affecting the sound.

 

The bottom row is run by the CPU to control tempo and a simple waveform.

Edited December 10, 2017 by karri

[StinkerB06]

 

Of course.

 

You can download a visual tool to access all the registers from http://www.ataritimes.com/index.php?ArticleIDX=418

 

I wrote this in 2004 and all the register bits are easily accessible from a graphical interface.

 

Screenshot from 2017-12-10 21-37-52.png

 

The top row contains the hardware bits affecting the sound.

 

The bottom row is run by the CPU to control tempo and a simple waveform.

What's a ".o" file?

[+karri]

An ".o" file is a file that you can upload to the Lynx using the ComLynx interface. It has a small header that is also called the BLL header.

 

In a time when the encryption process was not fully understood one of the ways to run unsigned code on the Lynx was to build it ComLynx uploaders into hobby cart releases like S.I.M.I.S.

 

It is a bit tricky to convert it to a .lnx file so I will do it for you.

 

 

abclnx.zip

[StinkerB06]

An ".o" file is a file that you can upload to the Lynx using the ComLynx interface. It has a small header that is also called the BLL header.

 

In a time when the encryption process was not fully understood one of the ways to run unsigned code on the Lynx was to build it ComLynx uploaders into hobby cart releases like S.I.M.I.S.

 

It is a bit tricky to convert it to a .lnx file so I will do it for you.

 

 

Will not work on mednafen

[+karri]

Will not work on mednafen

Oh yes it works on Mednafen. Proof below. You just have to unzip the file before using it.

[StinkerB06]

Oh yes it works on Mednafen. Proof below. You just have to unzip the file before using it.

I did unzip the file. Well, as of whatever I'm doing, I'm using an extension to Mednafen called Mednaffe, which is just a GUI wrapper for Mednafen. I tried to run it here on Windows.

[+karri]

Too bad. It is 10 years since I stopped using Windows. Cannot help you on this one.