Megalextoria
Retro computing and gaming, sci-fi books, tv and movies and other geeky stuff.

Home » Digital Archaeology » Computer Arcana » Apple » Apple II » Please test 23k cassette encoding
Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend 
Switch to threaded view of this topic Create a new topic Submit Reply
Please test 23k cassette encoding [message #355388] Sun, 22 October 2017 13:23 Go to next message
Anonymous
Karma:
Originally posted by: raph.levien

Hi all,

I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:

http://levien.com/23k_test.wav

It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.

Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.

Many thanks,

Raph
Re: Please test 23k cassette encoding [message #355395 is a reply to message #355388] Sun, 22 October 2017 14:40 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
> Hi all,
>
> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>
> http://levien.com/23k_test.wav
>
> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>
> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>
> Many thanks,
>
> Raph

Could you put it in a downloadable zip file?
Re: Please test 23k cassette encoding [message #355407 is a reply to message #355395] Sun, 22 October 2017 15:36 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

On Sunday, October 22, 2017 at 2:40:44 PM UTC-4, James Davis wrote:
> On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
>> Hi all,
>>
>> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>>
>> http://levien.com/23k_test.wav
>>
>> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>>
>> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>>
>> Many thanks,
>>
>> Raph
>
> Could you put it in a downloadable zip file?

Done: http://levien.com/23k_test.zip
Re: Please test 23k cassette encoding [message #355409 is a reply to message #355407] Sun, 22 October 2017 15:57 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Sunday, October 22, 2017 at 12:36:05 PM UTC-7, raph....@gmail.com wrote:
> On Sunday, October 22, 2017 at 2:40:44 PM UTC-4, James Davis wrote:
>> On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
>>> Hi all,
>>>
>>> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>>>
>>> http://levien.com/23k_test.wav
>>>
>>> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>>>
>>> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>>>
>>> Many thanks,
>>>
>>> Raph
>>
>> Could you put it in a downloadable zip file?
>
> Done: http://levien.com/23k_test.zip

Thanks.

As soon as I can figure out why I keep getting "Syntax Errors" when trying to "Load" from the Applesoft prompt on my Enhanced Apple //e, I'll let you know what I can about it.
Re: Please test 23k cassette encoding [message #355621 is a reply to message #355409] Mon, 23 October 2017 11:13 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 10/22/17 1:57 PM, James Davis wrote:

> As soon as I can figure out why I keep getting "Syntax Errors" when trying to "Load" from the Applesoft prompt on my Enhanced Apple //e, I'll let you know what I can about it.

Do not boot an OS. Remove any floppies, power on, ctrl-reset, then LOAD
Re: Please test 23k cassette encoding [message #355643 is a reply to message #355621] Mon, 23 October 2017 16:14 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Monday, October 23, 2017 at 8:13:13 AM UTC-7, Egan Ford wrote:
> On 10/22/17 1:57 PM, James Davis wrote:
>
>> As soon as I can figure out why I keep getting "Syntax Errors" when trying to "Load" from the Applesoft prompt on my Enhanced Apple //e, I'll let you know what I can about it.
>
> Do not boot an OS. Remove any floppies, power on, ctrl-reset, then LOAD

Problem is, it boots from my Sider in slot-7. I'll have to see if ctrl+reset will drop out of ProSel or just reboot. I'll let you know later.
Re: Please test 23k cassette encoding [message #355665 is a reply to message #355388] Tue, 24 October 2017 04:36 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
> Hi all,
>
> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>
> http://levien.com/23k_test.wav
>
> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>
> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>
> Many thanks,
>
> Raph

Raph,

I got your wave file to load. Took about 5 seconds, counting 1-1000, 2-1000, etc. Final result: a hi-res picture of random dots/dashes of colors/white/black. I did not see two pictures, or if I did, I did not see a change from one to the other, IIRC, but I was not watching very closely.

I used an audio cable from my Lenovo PC to my Enhanced Apple //e. I extracted the 23k_test.wav file from 23k_test.zip using 7-zip. Played the 23k_test.wav file using (default) Windows Media Player. Speaker volume was set to 50% with no enhancements. [This is the same volume that I used to bootstrap ADT ProDOS.]

I had to turn off my Apple //e to get out from under your program and then turn it back on to park my Sider HDD heads. My Apple //e kept dropping into the monitor after escaping your program instead of cold/warm starting when I pressed ctrl+reset or ctrl+apple+reset.

I think it might be easier to see changes if you had two pictures of real things that are different from each other but very recognizable (like your "mug shot," front and profile, with a placard numbered one and two [ ;-) & )-; ], LOL). Then, if there were errors, they would not look as good (as you), full of holes (random dots/dashes of colors/white/black). You could show each picture for a few seconds each, repeatedly until escape is pressed, then exit to Applesoft/Integer BASIC via the cold start entry vector ($E000). [That is what I had to do after booting up ProDOS/ProSel and dropping into Applesoft, then into the Monitor ( ]Call-155 then *E000G ) before I could LOAD successfully. Later, I realized that all I really had to do was to turn off my Sider before turning on my Apple //e.]

James Davis
Re: Please test 23k cassette encoding [message #355674 is a reply to message #355665] Tue, 24 October 2017 12:31 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

On Tuesday, October 24, 2017 at 4:36:03 AM UTC-4, James Davis wrote:
> On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
>> Hi all,
>>
>> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>>
>> http://levien.com/23k_test.wav
>>
>> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>>
>> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>>
>> Many thanks,
>>
>> Raph
>
> Raph,
>
> I got your wave file to load. Took about 5 seconds, counting 1-1000, 2-1000, etc. Final result: a hi-res picture of random dots/dashes of colors/white/black. I did not see two pictures, or if I did, I did not see a change from one to the other, IIRC, but I was not watching very closely.
>
> I used an audio cable from my Lenovo PC to my Enhanced Apple //e. I extracted the 23k_test.wav file from 23k_test.zip using 7-zip. Played the 23k_test.wav file using (default) Windows Media Player. Speaker volume was set to 50% with no enhancements. [This is the same volume that I used to bootstrap ADT ProDOS.]
>
> I had to turn off my Apple //e to get out from under your program and then turn it back on to park my Sider HDD heads. My Apple //e kept dropping into the monitor after escaping your program instead of cold/warm starting when I pressed ctrl+reset or ctrl+apple+reset.
>
> I think it might be easier to see changes if you had two pictures of real things that are different from each other but very recognizable (like your "mug shot," front and profile, with a placard numbered one and two [ ;-) & )-; ], LOL). Then, if there were errors, they would not look as good (as you), full of holes (random dots/dashes of colors/white/black). You could show each picture for a few seconds each, repeatedly until escape is pressed, then exit to Applesoft/Integer BASIC via the cold start entry vector ($E000). [That is what I had to do after booting up ProDOS/ProSel and dropping into Applesoft, then into the Monitor ( ]Call-155 then *E000G ) before I could LOAD successfully. Later, I realized that all I really had to do was to turn off my Sider before turning on my Apple //e.]
>
> James Davis

Thanks, that's at least one data point confirming my suspicion that the encoding is too sensitive to calibration differences.

I've redone the encoding completely, getting rid of the asymmetry, and have samples here:

http://levien.com/20ktest.zip

The encoding is sensitive to polarity, so I've put both polarities in there..

I'm excited about the new encoding, because I think it will be quite robust (probably more so even than the 8k encoding in c2t). I've already confirmed that it can play at 44.1k and 48k sampling rates.

Raph
Re: Please test 23k cassette encoding [message #355696 is a reply to message #355674] Tue, 24 October 2017 19:59 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Tuesday, October 24, 2017 at 9:31:17 AM UTC-7, raph....@gmail.com wrote:
> On Tuesday, October 24, 2017 at 4:36:03 AM UTC-4, James Davis wrote:
>> On Sunday, October 22, 2017 at 10:23:48 AM UTC-7, raph....@gmail.com wrote:
>>> Hi all,
>>>
>>> I've packaged together an easy-to-do test for the 23k encoding I've prototyped and have been discussing here. Just type "LOAD" from the BASIC prompt and play this file into the cassette port:
>>>
>>> http://levien.com/23k_test.wav
>>>
>>> It contains two copies of an image file. If there are bit errors, then you'll see some of the pixels change from the first copy to the second - I see this when the volume is outside the reliable range.
>>>
>>> Let me know failure/success, what kind of Apple you have, what your sound output device is, and what range of volumes seem to work.
>>>
>>> Many thanks,
>>>
>>> Raph
>>
>> Raph,
>>
>> I got your wave file to load. Took about 5 seconds, counting 1-1000, 2-1000, etc. Final result: a hi-res picture of random dots/dashes of colors/white/black. I did not see two pictures, or if I did, I did not see a change from one to the other, IIRC, but I was not watching very closely.
>>
>> I used an audio cable from my Lenovo PC to my Enhanced Apple //e. I extracted the 23k_test.wav file from 23k_test.zip using 7-zip. Played the 23k_test.wav file using (default) Windows Media Player. Speaker volume was set to 50% with no enhancements. [This is the same volume that I used to bootstrap ADT ProDOS.]
>>
>> I had to turn off my Apple //e to get out from under your program and then turn it back on to park my Sider HDD heads. My Apple //e kept dropping into the monitor after escaping your program instead of cold/warm starting when I pressed ctrl+reset or ctrl+apple+reset.
>>
>> I think it might be easier to see changes if you had two pictures of real things that are different from each other but very recognizable (like your "mug shot," front and profile, with a placard numbered one and two [ ;-) & )-; ], LOL). Then, if there were errors, they would not look as good (as you), full of holes (random dots/dashes of colors/white/black). You could show each picture for a few seconds each, repeatedly until escape is pressed, then exit to Applesoft/Integer BASIC via the cold start entry vector ($E000). [That is what I had to do after booting up ProDOS/ProSel and dropping into Applesoft, then into the Monitor ( ]Call-155 then *E000G ) before I could LOAD successfully. Later, I realized that all I really had to do was to turn off my Sider before turning on my Apple //e.]
>>
>> James Davis
>
> Thanks, that's at least one data point confirming my suspicion that the encoding is too sensitive to calibration differences.
>
> I've redone the encoding completely, getting rid of the asymmetry, and have samples here:
>
> http://levien.com/20ktest.zip
>
> The encoding is sensitive to polarity, so I've put both polarities in there.
>
> I'm excited about the new encoding, because I think it will be quite robust (probably more so even than the 8k encoding in c2t). I've already confirmed that it can play at 44.1k and 48k sampling rates.
>
> Raph

Raph,

I have retested with all of your wave files: 23k, 20k & inverse. All were consistently successful at 90% speaker volume, using the same hardware/software as stated before/above in this thread. [I had to turn my Enhanced Apple //e off and on each time between tests. Otherwise, after ctrl+reset, a second LOAD would crash into the monitor (* prompt) and continue to do so, no matter what. You need to write a more turnkey application to prevent this.] I got 10 good clean vertical white bars (and 9 or 10 black bars) across the screen. The outer edges of the white bars had some color fringing (green on right side, cyan on left side, 1 pixel wide, on each bar). At 100% volume, I got some noise. At 75% volume, I got LOAD ERRORS. The 100% volume noise was random color pixels within the vertical bar pattern; mostly confined to three 4-square (2x2) Low-Res block areas within the white bar areas. At 50% volume was my previous un-"successful" tests as described above; but, that was probably because I had booted into ProDOS/ProSel first before restarting Applesoft Cold.

I hope this helps,

James Davis
Re: Please test 23k cassette encoding [message #355697 is a reply to message #355696] Tue, 24 October 2017 20:11 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

P.S. So, how is this useful if I have to turn my computer off and on again to do anything else with the computer?
Re: Please test 23k cassette encoding [message #355807 is a reply to message #355697] Tue, 24 October 2017 20:38 Go to previous messageGo to next message
Michael J. Mahon is currently offline  Michael J. Mahon
Messages: 1767
Registered: October 2012
Karma: 0
Senior Member
James Davis <JPD.Enterprises@outlook.com> wrote:
> P.S. So, how is this useful if I have to turn my computer off and on
> again to do anything else with the computer?
>

This is a test. This is *only* a test. ;-)

--
-michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com
Re: Please test 23k cassette encoding [message #355812 is a reply to message #355807] Tue, 24 October 2017 21:23 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Tuesday, October 24, 2017 at 5:38:51 PM UTC-7, Michael J. Mahon wrote:
> James Davis wrote:
>> P.S. So, how is this useful if I have to turn my computer off and on
>> again to do anything else with the computer?
>>
>
> This is a test. This is *only* a test. ;-)
>
> --
> -michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com

Yes, I know, but it would be nice if the test had a proper exit and didn't lock up the computer; e.g., "Press any key" to return to Applesoft/Integer BASIC; so one could LOAD again and again--to test more than once and/or to test more frequencies--without having to power down each time. My switch is pretty old. I don't want to break it.
Re: Please test 23k cassette encoding [message #355817 is a reply to message #355812] Tue, 24 October 2017 23:05 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

On Tuesday, October 24, 2017 at 9:23:54 PM UTC-4, James Davis wrote:
> On Tuesday, October 24, 2017 at 5:38:51 PM UTC-7, Michael J. Mahon wrote:
>> James Davis wrote:
>>> P.S. So, how is this useful if I have to turn my computer off and on
>>> again to do anything else with the computer?
>>>
>>
>> This is a test. This is *only* a test. ;-)
>>
>> --
>> -michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com
>
> Yes, I know, but it would be nice if the test had a proper exit and didn't lock up the computer; e.g., "Press any key" to return to Applesoft/Integer BASIC; so one could LOAD again and again--to test more than once and/or to test more frequencies--without having to power down each time. My switch is pretty old. I don't want to break it.

Hmm, Ctrl-Openapple-Reset works for me. I could probably tweak the test code to add a proper exit though.

You're not seeing a photo of an Apple computer? That's what you're _supposed_ to see.

Also, do you know if any of the faster c2t modes work for you? So far I've gotten the old (non -96h) 8k mode to work, but none of the others. It's starting to look like there's a wide variation from machine to machine.

Raph
Re: Please test 23k cassette encoding [message #355823 is a reply to message #355388] Thu, 26 October 2017 11:24 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

On Wednesday, October 25, 2017 at 4:53:42 PM UTC-4, Egan Ford wrote:
> On 10/24/17 9:05 PM, raph.levien@gmail.com wrote:
>
>> Also, do you know if any of the faster c2t modes work for you? So far I've gotten the old (non -96h) 8k mode to work, but none of the others. It's starting to look like there's a wide variation from machine to machine.
>
> What are you using to play the audio of the 9.6K mode? Can you try a
> different audio player?

I'm using sox directly to the USB audio device (the built-in DAC in the Dell P2715Q monitor). I've used a scope to verify that this is an accurate, high-quality path with no additional effects.

But I do have some more insight into what's going wrong. Both -8 and -f modes (in c2t-96h) work when polarity is inverted (-v -0.5 in sox). This seems to be a characteristic of these fancier sense loops, they're detecting particular transitions rather than flips as in the Apple encoding. I noticed that Jorge's demo has an "invert" button. For me, it worked at the normal setting.

I'm wondering if this might be a systematic reason people have trouble with the faster c2t modes.
Re: Please test 23k cassette encoding [message #355826 is a reply to message #355388] Wed, 25 October 2017 02:14 Go to previous messageGo to next message
bpiltz is currently offline  bpiltz
Messages: 78
Registered: October 2012
Karma: 0
Member
I'm going to test this, it has great interest to me, as my transfers to my Apple are limited to the cassette port, as I do not have a SSC.

Using ADTPro is *painfully* slow, a 40-track disk takes ~10 minutes or longer to transfer over.

If your method, at 23kbit/sec is viable, it will improve this time to under a minute! I anxiously look forward to that day. Your efforts are truly appreciated.

Please excuse my tardiness in testing, as I want to wait until this terrible 105-degree heatwave is over first. Then I'll be able to function and provide you the necessary and proper feedback.
Re: Please test 23k cassette encoding [message #355827 is a reply to message #355817] Wed, 25 October 2017 03:01 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Tuesday, October 24, 2017 at 8:05:44 PM UTC-7, raph....@gmail.com wrote:
> On Tuesday, October 24, 2017 at 9:23:54 PM UTC-4, James Davis wrote:
>> On Tuesday, October 24, 2017 at 5:38:51 PM UTC-7, Michael J. Mahon wrote:
>>> James Davis wrote:
>>>> P.S. So, how is this useful if I have to turn my computer off and on
>>>> again to do anything else with the computer?
>>>>
>>>
>>> This is a test. This is *only* a test. ;-)
>>>
>>> --
>>> -michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com
>>
>> Yes, I know, but it would be nice if the test had a proper exit and didn't lock up the computer; e.g., "Press any key" to return to Applesoft/Integer BASIC; so one could LOAD again and again--to test more than once and/or to test more frequencies--without having to power down each time. My switch is pretty old. I don't want to break it.
>
> Hmm, Ctrl-Openapple-Reset works for me. I could probably tweak the test code to add a proper exit though.
>
> You're not seeing a photo of an Apple computer? That's what you're _supposed_ to see.
>
> Also, do you know if any of the faster c2t modes work for you? So far I've gotten the old (non -96h) 8k mode to work, but none of the others. It's starting to look like there's a wide variation from machine to machine.
>
> Raph

So, you are saying that what I am seeing is not what I am supposed to be seeing, that my tests have been unsuccessful. Please include a JPEG picture of it in the next zip. CyderPress or Buckshot can convert the Hi-Res picture to a Bitmapped picture, and MS Paint can then save it as a JPG picture. You have got me wondering if there are more things going wrong with my old Apple IIe than just not being able to get ADT ProDOS server to hear the audio cassette output from it. I'll have to see if I have some HI-RES pictures on my HDD that I can view to test that, too. I can't imagine why I would get 10 perfect vertical white stripes instead of a good or bad picture of an Apple II. If I ever get a good result, I'll let you know.
Re: Please test 23k cassette encoding [message #355828 is a reply to message #355817] Wed, 25 October 2017 16:53 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 10/24/17 9:05 PM, raph.levien@gmail.com wrote:

> Also, do you know if any of the faster c2t modes work for you? So far I've gotten the old (non -96h) 8k mode to work, but none of the others. It's starting to look like there's a wide variation from machine to machine.

What are you using to play the audio of the 9.6K mode? Can you try a
different audio player?
Re: Please test 23k cassette encoding [message #355829 is a reply to message #355826] Wed, 25 October 2017 17:03 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 10/25/17 12:14 AM, bpiltz@gmail.com wrote:
> I'm going to test this, it has great interest to me, as my transfers to my Apple are limited to the cassette port, as I do not have a SSC.
>
> Using ADTPro is *painfully* slow, a 40-track disk takes ~10 minutes or longer to transfer over.
>
> If your method, at 23kbit/sec is viable, it will improve this time to under a minute! I anxiously look forward to that day. Your efforts are truly appreciated.
>
> Please excuse my tardiness in testing, as I want to wait until this terrible 105-degree heatwave is over first. Then I'll be able to function and provide you the necessary and proper feedback.
>

Are you transferring Apple II to image or image to Apple II, if the
later, then consider using c2t(-96h) (8000-9600bps). With c2t builtin
compression the effective BPS rate has been measured as high as 40000
bps. The average effective bps rate is 19000 based on 1500
virtualapple.org games.

Effective BPS rate is based on the time to transfer and decompress the
data. Not the time to write to disk.
Re: Please test 23k cassette encoding [message #355830 is a reply to message #355827] Wed, 25 October 2017 13:01 Go to previous messageGo to next message
Michael AppleWin Debu is currently offline  Michael AppleWin Debu
Messages: 1262
Registered: March 2013
Karma: 0
Senior Member
> I think it might be easier to see changes if you had two pictures of real things that are different from each other but very recognizable (like your "mug shot," front and profile, with a placard numbered one and two [ ;-) & )-; ], LOL).

> So, you are saying that what I am seeing is not what I am supposed to be seeing, that my tests have been unsuccessful. Please include a JPEG picture of it in the next zip. CyderPress or Buckshot can convert the Hi-Res picture to a Bitmapped picture, and MS Paint can then save it as a JPG picture..

You guys are making this WAY more complicated then necessary.
Clear the HGR screen to a solid color and you can easily tell the order:

; Clear to Green
ORG $300
LDA #2A
STA $1C
LDA #$20
JMP $F3F6

; Clear to Blue
LDA #D5
STA $1C
LDA #$20
JMP $F3F6

; Colors:
; 2A = Green
; 55 = Magenta
; AA = Orange
; D5 = Blue

Hexdump:

300:A9 2A 85 1C A9 20 4C F6 F3
309:A9 D5 85 1C A9 20 4C F6 F3
Re: Please test 23k cassette encoding [message #355836 is a reply to message #355830] Wed, 25 October 2017 15:56 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

On Wednesday, October 25, 2017 at 10:01:50 AM UTC-7, Michael 'AppleWin Debugger Dev' wrote:
>> I think it might be easier to see changes if you had two pictures of real things that are different from each other but very recognizable (like your "mug shot," front and profile, with a placard numbered one and two [ ;-) & )-; ], LOL).
>
>> So, you are saying that what I am seeing is not what I am supposed to be seeing, that my tests have been unsuccessful. Please include a JPEG picture of it in the next zip. CyderPress or Buckshot can convert the Hi-Res picture to a Bitmapped picture, and MS Paint can then save it as a JPG picture.
>
> You guys are making this WAY more complicated then necessary.
> Clear the HGR screen to a solid color and you can easily tell the order:
>
> ; Clear to Green
> ORG $300
> LDA #2A
> STA $1C
> LDA #$20
> JMP $F3F6
>
> ; Clear to Blue
> LDA #D5
> STA $1C
> LDA #$20
> JMP $F3F6
>
> ; Colors:
> ; 2A = Green
> ; 55 = Magenta
> ; AA = Orange
> ; D5 = Blue
>
> Hexdump:
>
> 300:A9 2A 85 1C A9 20 4C F6 F3
> 309:A9 D5 85 1C A9 20 4C F6 F3

Michael: "... [than] necessary." You got it right the other day when you thanked me, but wrong ever since. Please, do not take offense. I know how hard it is to break old habits.

Raph: Does Michael's code help you?

James Davis
Re: Please test 23k cassette encoding [message #355838 is a reply to message #355836] Wed, 25 October 2017 17:06 Go to previous messageGo to next message
Michael AppleWin Debu is currently offline  Michael AppleWin Debu
Messages: 1262
Registered: March 2013
Karma: 0
Senior Member
On Wednesday, October 25, 2017 at 12:56:44 PM UTC-7, James Davis wrote:
> Michael: "... [than] necessary." You got it right the other day when you thanked me, but wrong ever since. Please, do not take offense. I know how hard it is to break old habits.

No worries. No offense taken. That completely slipped under my radar.

I see that this will be my bane until my end of days. :-(
Re: Please test 23k cassette encoding [message #355850 is a reply to message #355838] Thu, 26 October 2017 23:52 Go to previous messageGo to next message
Steve Nickolas is currently offline  Steve Nickolas
Messages: 2036
Registered: October 2012
Karma: 0
Senior Member
On Wed, 25 Oct 2017, Michael 'AppleWin Debugger Dev' wrote:

> On Wednesday, October 25, 2017 at 12:56:44 PM UTC-7, James Davis wrote:
>> Michael: "... [than] necessary." You got it right the other day when you thanked me, but wrong ever since. Please, do not take offense. I know how hard it is to break old habits.
>
> No worries. No offense taken. That completely slipped under my radar.
>
> I see that this will be my bane until my end of days. :-(

I have a friend with very precise UK English who nonetheless almost never
spells words with the combination C-E-I correctly. :P

-uso.
Re: Please test 23k cassette encoding [message #356280 is a reply to message #355823] Tue, 31 October 2017 20:25 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: James Davis

So raph, are there any more tests you wand done? What's happened in the last week? Have you made any progress?
Re: Please test 23k cassette encoding [message #356282 is a reply to message #356280] Tue, 31 October 2017 21:15 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

On Tuesday, October 31, 2017 at 8:25:15 PM UTC-4, James Davis wrote:
> So raph, are there any more tests you wand done? What's happened in the last week? Have you made any progress?

I don't have much to show publicly from the last week - I've started integrating the sense code into c2t proper, but it's non-trivial. I'd like to see results from at least one or two other machines - if I can't get this to work on any machine other than the one at Recurse Center, it demotivates me.

One idea I'm toying with is to write a separate standalone utility (shipped as a wav file that you can LOAD) that characterizes the audio connection. My basic idea is to have a sense core that samples a few milliseconds of sound into a small memory buffer, then an analysis pass that basically measures duty cycle and jitter. Then the audio file contains a whole bunch of test tones, including at different amplitudes to test sensitivity to volume.

I'm a bit busy with other things, not sure exactly when this will happen. Thanks for your continued interest.
Re: Please test 23k cassette encoding [message #356306 is a reply to message #356282] Wed, 01 November 2017 12:11 Go to previous messageGo to next message
Michael J. Mahon is currently offline  Michael J. Mahon
Messages: 1767
Registered: October 2012
Karma: 0
Senior Member
<raph.levien@gmail.com> wrote:
> On Tuesday, October 31, 2017 at 8:25:15 PM UTC-4, James Davis wrote:
>> So raph, are there any more tests you wand done? What's happened in the
>> last week? Have you made any progress?
>
> I don't have much to show publicly from the last week - I've started
> integrating the sense code into c2t proper, but it's non-trivial. I'd
> like to see results from at least one or two other machines - if I can't
> get this to work on any machine other than the one at Recurse Center, it demotivates me.
>
> One idea I'm toying with is to write a separate standalone utility
> (shipped as a wav file that you can LOAD) that characterizes the audio
> connection. My basic idea is to have a sense core that samples a few
> milliseconds of sound into a small memory buffer, then an analysis pass
> that basically measures duty cycle and jitter. Then the audio file
> contains a whole bunch of test tones, including at different amplitudes
> to test sensitivity to volume.
>
> I'm a bit busy with other things, not sure exactly when this will happen.
> Thanks for your continued interest.
>
>

Great idea--actually measuring the cassette input response for a particular
player/computer combo!

--
-michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com
Re: Please test 23k cassette encoding [message #357262 is a reply to message #356306] Sun, 19 November 2017 19:04 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: raph.levien

I've been experimenting and thinking more on this, and my latest thoughts are here:

https://github.com/datajerk/c2t/issues/4

Quick summary: I've identified polarity inversion as a serious problem; I'm trying to figure out how to balance 6502 code size against other factors; and I'm seeking input on whether to try to ship something in the 16kbps range with relatively simple waveform generation (but which would be much more reliable than the 23kpbs prototype I first posted), or whether keep pushing on the engineering to get the speeds high.
Re: Please test 23k cassette encoding [message #357279 is a reply to message #357262] Tue, 21 November 2017 12:27 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 11/19/17 5:04 PM, raph.levien@gmail.com wrote:
> I've been experimenting and thinking more on this, and my latest thoughts are here:
>
> https://github.com/datajerk/c2t/issues/4
>
> Quick summary: I've identified polarity inversion as a serious problem; I'm trying to figure out how to balance 6502 code size against other factors; and I'm seeking input on whether to try to ship something in the 16kbps range with relatively simple waveform generation (but which would be much more reliable than the 23kpbs prototype I first posted), or whether keep pushing on the engineering to get the speeds high.
>

I'd start with 16kbps and get as many as possible to test. There is
variation between players and IIs.
Re: Please test 23k cassette encoding [message #363069 is a reply to message #355388] Sat, 10 February 2018 05:15 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Jorge

How is this freaking awesome thing going? Any progress?
Re: Please test 23k cassette encoding [message #363256 is a reply to message #363069] Mon, 12 February 2018 06:44 Go to previous messageGo to next message
STYNX is currently offline  STYNX
Messages: 453
Registered: October 2012
Karma: 0
Senior Member
On Saturday, 10 February 2018 11:15:59 UTC+1, Jorge wrote:
> How is this freaking awesome thing going? Any progress?

Im interested in the result as well. I wonder if acceleration (TW, Zipchip) could allow for more speed?
A high speed LOAD feature via tape interface for ADTpro would be nice :-)

Something like: first load a mini loader over the normal A2 LOAD method and then execute the mini loader for high speed loading...

-Jonas
Re: Please test 23k cassette encoding [message #363290 is a reply to message #363256] Mon, 12 February 2018 14:19 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Jorge

On Monday, February 12, 2018 at 12:44:39 PM UTC+1, STYNX wrote:
> On Saturday, 10 February 2018 11:15:59 UTC+1, Jorge wrote:
>> How is this freaking awesome thing going? Any progress?
>
> Im interested in the result as well. I wonder if acceleration (TW, Zipchip) could allow for more speed?
> A high speed LOAD feature via tape interface for ADTpro would be nice :-)
>
> Something like: first load a mini loader over the normal A2 LOAD method and then execute the mini loader for high speed loading...

The web site of Egan Ford does that already: http://asciiexpress.net/diskserver/ but the audio encoding he's using is not very reliable.

I think a zipchip won't help much because the problem is the audio in hardware of the Apple II and the audio out hardware of a PC/Mac/Phone, more than the speed of the Apple II cpu. The speed limit is around 14 kbps max IMHO.

--
Jorge.
Re: Please test 23k cassette encoding [message #363292 is a reply to message #355388] Mon, 12 February 2018 14:36 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Jorge

Well I mean about 14 kbps max wire speed, if on top of that you add compression then a zipchip may be a good thing to avoid additional inter frame delays while decompressing the packets.
Re: Please test 23k cassette encoding [message #363318 is a reply to message #363290] Mon, 12 February 2018 22:35 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 2/12/18 12:19 PM, Jorge wrote:
> On Monday, February 12, 2018 at 12:44:39 PM UTC+1, STYNX wrote:
>> On Saturday, 10 February 2018 11:15:59 UTC+1, Jorge wrote:
>>> How is this freaking awesome thing going? Any progress?
>>
>> Im interested in the result as well. I wonder if acceleration (TW, Zipchip) could allow for more speed?
>> A high speed LOAD feature via tape interface for ADTpro would be nice :-)
>>
>> Something like: first load a mini loader over the normal A2 LOAD method and then execute the mini loader for high speed loading...
>
> The web site of Egan Ford does that already: http://asciiexpress.net/diskserver/ but the audio encoding he's using is not very reliable.

I beg to differ. It is quite reliable. There are a few edge cases with
9600 BPS and older players. 8000 BPS has no known outstanding issues
that I can recall.
Re: Please test 23k cassette encoding [message #363336 is a reply to message #363318] Tue, 13 February 2018 05:02 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Jorge

On Tuesday, February 13, 2018 at 4:34:49 AM UTC+1, Egan Ford wrote:
> On 2/12/18 12:19 PM, Jorge wrote:
>>
>> The web site of Egan Ford does that already: http://asciiexpress.net/diskserver/ but the audio encoding he's using is not very reliable.
>
> I beg to differ. It is quite reliable. There are a few edge cases with
> 9600 BPS and older players. 8000 BPS has no known outstanding issues
> that I can recall.

Oh, sorry. I say so because it didn't work so well for me. You have to find the proper volume setting and that's very very tricky. As I told you before when it works it's great.
Re: Please test 23k cassette encoding [message #363381 is a reply to message #363336] Tue, 13 February 2018 16:07 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 2/13/18 3:02 AM, Jorge wrote:
> On Tuesday, February 13, 2018 at 4:34:49 AM UTC+1, Egan Ford wrote:
>> On 2/12/18 12:19 PM, Jorge wrote:
>>>
>>> The web site of Egan Ford does that already: http://asciiexpress.net/diskserver/ but the audio encoding he's using is not very reliable.
>>
>> I beg to differ. It is quite reliable. There are a few edge cases with
>> 9600 BPS and older players. 8000 BPS has no known outstanding issues
>> that I can recall.
>
> Oh, sorry. I say so because it didn't work so well for me. You have to find the proper volume setting and that's very very tricky. As I told you before when it works it's great.

AFAIK, for everyone else max volume works.
Re: Please test 23k cassette encoding [message #363475 is a reply to message #363381] Wed, 14 February 2018 15:40 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Jorge

On Tuesday, February 13, 2018 at 10:07:22 PM UTC+1, Egan Ford wrote:
> On 2/13/18 3:02 AM, Jorge wrote:
>>
>> Oh, sorry. I say so because it didn't work so well for me. You have to find the proper volume setting and that's very very tricky. As I told you before when it works it's great.
>
> AFAIK, for everyone else max volume works.

Sorry, but I doubt it, scope in hand I've seen that the DC component of your audio files is very critical it lengthens/shortens pulses ~ randomly (depends on the data being sent because the dc component of the "one" symbol is not zero) and that produces receive errors. So the 9600 waveforms almost never work (with reason), and the 8000 bps (symbols are symmetrical -> no DC component) only after a few tries tweaking the volume to get it exactly right, because it does not account for the delay of the opamp when/if it goes into saturation.
Re: Please test 23k cassette encoding [message #363571 is a reply to message #363475] Thu, 15 February 2018 19:44 Go to previous messageGo to next message
Egan Ford is currently offline  Egan Ford
Messages: 304
Registered: October 2012
Karma: 0
Senior Member
On 2/14/18 1:40 PM, Jorge wrote:
> On Tuesday, February 13, 2018 at 10:07:22 PM UTC+1, Egan Ford wrote:
>> On 2/13/18 3:02 AM, Jorge wrote:
>>>
>>> Oh, sorry. I say so because it didn't work so well for me. You have to find the proper volume setting and that's very very tricky. As I told you before when it works it's great.
>>
>> AFAIK, for everyone else max volume works.
>
> Sorry, but I doubt it, scope in hand I've seen that the DC component of your audio files is very critical it lengthens/shortens pulses ~ randomly (depends on the data being sent because the dc component of the "one" symbol is not zero) and that produces receive errors. So the 9600 waveforms almost never work (with reason), and the 8000 bps (symbols are symmetrical -> no DC component) only after a few tries tweaking the volume to get it exactly right, because it does not account for the delay of the opamp when/if it goes into saturation.

You're doubting the 100s (perhaps 1000s) of people that haven't had any
problems.
Re: Please test 23k cassette encoding [message #363572 is a reply to message #363571] Thu, 15 February 2018 19:51 Go to previous message
anthonypaulo is currently offline  anthonypaulo
Messages: 531
Registered: September 2013
Karma: 0
Senior Member
On Thursday, February 15, 2018 at 7:44:49 PM UTC-5, Egan Ford wrote:
> On 2/14/18 1:40 PM, Jorge wrote:
>> On Tuesday, February 13, 2018 at 10:07:22 PM UTC+1, Egan Ford wrote:
>>> On 2/13/18 3:02 AM, Jorge wrote:
>>>>
>>>> Oh, sorry. I say so because it didn't work so well for me. You have to find the proper volume setting and that's very very tricky. As I told you before when it works it's great.
>>>
>>> AFAIK, for everyone else max volume works.
>>
>> Sorry, but I doubt it, scope in hand I've seen that the DC component of your audio files is very critical it lengthens/shortens pulses ~ randomly (depends on the data being sent because the dc component of the "one" symbol is not zero) and that produces receive errors. So the 9600 waveforms almost never work (with reason), and the 8000 bps (symbols are symmetrical -> no DC component) only after a few tries tweaking the volume to get it exactly right, because it does not account for the delay of the opamp when/if it goes into saturation.
>
> You're doubting the 100s (perhaps 1000s) of people that haven't had any
> problems.

Millions!
  Switch to threaded view of this topic Create a new topic Submit Reply
Previous Topic: new Mockingboard demo (KSP theme)
Next Topic: SCSI2SD V6 fun
Goto Forum:
  

-=] Back to Top [=-
[ Syndicate this forum (XML) ] [ RSS ] [ PDF ]

Current Time: Fri Mar 29 10:58:57 EDT 2024

Total time taken to generate the page: 0.30645 seconds