19 replies to this topic

[morelenmir]

I don't want to report this is a definite bug on Avery's site until I know if other people and setups also experience it.

Firstly, I have disabled BASIC and then attached the 'Atari Assembler Editor' cartridge - keeping the disk drives attached and active. On attempting to load a source file through 'enter#d1:'... or an object file as 'load#d1:..., after the last beep from the loading process goes silent I get a constant high-pitched whistle from altirra. The same happens fairly regularly if I drop out to DOS XE and then exit back. It is definitely Altirra to blame as if I 'pause' the emulation the whistle stops. Interestingly the whistle can be stopped permanently by pressing system reset. It is also NOT related to the new 'drive sounds' functionality as the same occurs with v2.1 b9. It is a maddening, high pitch noise that i cannot bear to hear for more than a few seconds. I have pretty sensitive hearing so anyone else testing this situation out may need to turn up there speakers.

I am not certain it is a bug as such however. it could be my desktop's hardware setup. It could also be something to do with contrast like you used to get that buzz/whistle when the football results would scroll across the bottom of a television screen. It is a similar sound. Very high and very maddening.

To recap, I get this EVERY time when I load a source file in 'Atari Assembler Editor' and fairly often when saving a file or switching to DOS XE. It also happens with 'mac/65' under the same circumstances and I guess maybe any cartridge that takes text input and saves/loads to disk. I would be very interested to hear if anyone else gets this same sound under these conditions. For me it is pretty much a show-stopper as I cannot stand the sound and constantly having to system reset is equally irritating.

[Mclaneinc]

Hi there Morelenmir

I've just tried this with Altirra and not hearing the high pitched noise here, will try it on my daughter later as she's got super human hearing and I guess my tinnitus does not help

Paul from the Altirra blog...

[morelenmir]

Thanks for giving it a shot paul!!!

I have tried changing everything from roms to the sound output and still get it. I wonder if it is something specific to my setup like audio drivers or something? It is really putting a crimp into my Assembly-learning!!!

[Mclaneinc]

Pass, not had a chance to test it on my daughter BUT she is ultra sensitive to our TV when its set to an AV channel with no signal, she moans about a really high pitched noise from it which I can't hear, could be the same for you?

I thought you Yorkshire blokes were a hardy breed

[fibrewire]

Can you unplug your speakers and test the situation?

This applies to both CRT and LCD monitors. But in LCD, its the transformer for the CFL backlight that whines, or the EL in portables like the Newton Messagepad or Avigo 10. No noise from LED backlit monitors.

http://en.wikipedia....y_audible_noise

[morelenmir]

I know, i know... when it comes to high pitched sounds i am "r'eight Nesh mi'lad" - as my grandfather was given to saying!!!

I will give that a try fibrewire.

[Rybags]

Can you recreate the problem - run with Audio = Mono.

When you get the noise, hit F8 and get the debug window up.

Type .pokey

Then copy the output and paste it here. To copy from the debug window you have to select the text and hit CTRL-C.

[phaeron]

Can you enable the audio monitor and try toggling audio channels to see if any of them are the culprit? In particular, channels 3/4 being the issue would mean something wrong with SIO.

Also, try the global mute option, which kills all sound. If that works and turning off all the audio channels doesn't, then it's probably something like the new drive sound support I just added.

[morelenmir]

Many thanks for taking a quick look at this Avery - i did not want to bother you until I knew it was not just something wrong with my own system.

Okay. The whistle occurs with audio in either stereo or mono mode. With the audio monitor open - on 'enter#d1:'ing a source file in Assembler Editor - once the usual loading ticks have ended the first three channels, counting top to bottom fall back to zero whereas the forth channel shows a steady line above zero. Disabling channel 4 in the audio options stops the whistle.

This is the debug console output with audio set to mono and all four channels enabled:

Altirra> .pokey
AUDF1: 00 AUDC1: a0 Output: 1 (24 cycles until fire) (passive: 28 cycles)
AUDF2: 00 AUDC2: a0 Output: 0 (24 cycles until fire) (passive: 28 cycles)
AUDF3: 10 AUDC3: a0 Output: 1 (139 cycles until fire) (passive: 256 cycles)
AUDF4: 00 AUDC4: a8 Output: 1 (13 cycles until fire) (passive: 23 cycles)
AUDCTL: 28, 17-bit poly, 1.79 ch3, ch3+ch4, 64KHz
SKCTL: 03
SERIN: 5f
SEROUT: 68 (done)
shift register 68 (0: done)
IRQEN: c0, break key, keyboard
IRQST: f7, sertrans
ALLPOT: ff
Pot 0 will finish in 19427 cycles
Pot 1 will finish in 19427 cycles
Pot 2 will finish in 19427 cycles
Pot 3 will finish in 19427 cycles
Pot 4 will finish in 19427 cycles
Pot 5 will finish in 19427 cycles
Pot 6 will finish in 19427 cycles
Pot 7 will finish in 19427 cycles

Command line: negated

[phaeron]

It looks like this is a bug in DOS XE's high speed XF551 routine -- it leaves audio channel 4 on at the high speed rate of 39KHz, which is kind of lame. The problem is that Altirra's audio filter can't entirely filter it out. It's probably aliasing to somewhere in the 15-20KHz range, and therefore whether you can hear it depends on how much of your hearing you have left.

This doesn't happen for standard speed disk activity because the standard SIO routine shuts off audio channels when it is done. One workaround is to turn off the noisy SIO flag by setting SOUNDR ($41) to $00.

Edited by phaeron, Sat Feb 11, 2012 2:44 AM.

[morelenmir]

I'll give that a try Avery - or indeed maybe shift over to DOS 4.0. XE is a damn good DOS, but it certainly has its problems!!!

Many thanks for giving it a look.

Just an update...

Humorously enough it seems Assembler Editor doesn't like DOS 4.0! 'SpartaDOS' it is then - which in turn does not like XF551 in ultra speed... Nevermind. It WILL format at high speed (or I can shift to US Doubler emulation for Ultra), assembler editor gets on well with it and best of all one can save without the whistle!!!

Once again all thanks to Avery - this time for the foresight of allowing a secondary cartridge; slot one for sdx445 and slot two for a/e.

Edited by morelenmir, Sat Feb 11, 2012 11:36 AM.

[morelenmir]

I will just bump this the once.

I wondered why the whistle should only happen while saving with a cartridge 'inserted' and yet not while doing the same thing using BASIC?

[Rybags]

Fairly sure Basic clears the sound registers after a save operation, AsmEd doesn't.

If you're playing around with emulated assemblers, you'd be way better off using Mac-65.

[bfollett]

Somewhat related, there was some talk in this thread about why some can hear this high pitch tone and other can't. There is a website that has high pitched ringtones that teens can download. This lets them have their phones ring in school or home and adults can't hear it. They have sample tones at a different frequencies. I sadly no longer can hear above 12k... Maybe the slightest hint of 14K. Give it a try:
http://www.freemosquitoringtones.org/

Bob

[Rybags]

They're sine waves, a little hard to hear at the best of times. I got around 14-16 in that one too.

I just generated > 20 KHz square waves in Audacity and they're easy to hear.

The problem with using the computer to do this, you're limited by the sound hardware. If your gear only does 44.1 or 48 K/sec sample playback, then anything above about 20 KHz will sound the same anyway.

Additional to that, we'd be hitting the upper range that the speakers can handle. Such a test would be best done using earphones that are rated to reproduce high frequencies.

Edited by Rybags, Sun Feb 12, 2012 8:19 AM.

[Mclaneinc]

Is this the same tech they use to disperse anti social groups of kids?

I seem to remember you could buy a speaker of sorts that sent out a signal only they could hear which made it uncomfortable to stay around. They were not cheap, I'd love one for our block for when the little B*****s come in

[morelenmir]

That does make sense Rybags. Its all down to that sound channel. I wonder how that got passed the QA people!? Maybe they genuinely couldn't hear it.

I must have pretty good ears! I got down to 22 without any problem. Not bad for a doddering thirtysomething!!!

Edited by morelenmir, Sun Feb 12, 2012 9:59 AM.

[bfollett]

Mclaneinc, on Sun Feb 12, 2012 9:43 AM, said:

Is this the same tech they use to disperse anti social groups of kids?

I seem to remember you could buy a speaker of sorts that sent out a signal only they could hear which made it uncomfortable to stay around. They were not cheap, I'd love one for our block for when the little B*****s come in

I've heard that places like convenient stores would play these high tones loudly outside their buildings to keep teens from loitering. Nice to know these tones can be used by the adults too.

Bob

[Mclaneinc]

bfollett, on Sun Feb 12, 2012 10:09 AM, said:

Mclaneinc, on Sun Feb 12, 2012 9:43 AM, said:

Is this the same tech they use to disperse anti social groups of kids?

I seem to remember you could buy a speaker of sorts that sent out a signal only they could hear which made it uncomfortable to stay around. They were not cheap, I'd love one for our block for when the little B*****s come in

I've heard that places like convenient stores would play these high tones loudly outside their buildings to keep teens from loitering. Nice to know these tones can be used by the adults too.

Bob

No doubt some liberal do gooder has made sure a law is passed to stop young ears from suffering from these tones while the same teens spend all night making a racket and stopping everyone else from getting sleep.

I feel I should be elected as Judge Dredd

I'll cut down the teen attitude problem

[phaeron]

Yup, BASIC does clear the audio channels after a load. It doesn't on a save, but in that case the last disk operation is a write operation, and POKEY is left in asynchronous read mode which means channels 3+4 are locked.

As for high frequency noises, keep in mind that animals can hear these too. You might succeed in driving teens away, but you might also attract a curious dog, as I did once with a Tandy 1000.