Talk:Commodore Datasette

Formatting

Would there be any opposition to creating an images section on the page and moving most of the tape deck images down there rather than have them on the right side as thumbnails? The current layout causes page flow issues in the "Physical Coding" section of the page, the thumbnails crowd out the waveform image and cause it to overlap with some of the text. You can reproduce this by logging out of your account and viewing this page. I noticed when I logged in to fix the issue my user settings apparently changed the size of the thumbnails so they didn't crowd the waveform image. For anyone not logged into to WP the page flow error is potentially confusing. √2 (talk) 07:06, 16 February 2010 (UTC)

"Datassette" vs "Datasette"

The C64 Programmer's Ref Guide says "Datassette" (2 s'es)... --Wernher 02:54, 10 Jan 2004 (UTC)

... but various versions of the 1530/C2N's original packaging says both "Datasette" and "Datassette" (see Zimmers' pictures), and accordingly, that info is now duly included in the article. --Wernher 14:27, 11 Jan 2004 (UTC)

Cassette copying feasability

"Many a potential software pirate fancied themselves smart for trying to copy software recorded on tapes through an ordinary twin tape deck. This seldom met with success:"

This is rubbish, back in the 80s almost all my high school would exchange compliation tapes of games created by copying on twin tape decks. The tapes could normally survive at least 2 or 3 generations of copying too. --Anonymous

You're absolutely right; I can confirm this from ditto contemporary experiences in Norway. We even got usable results from playing the game cassette loudly on one deck and copying it via the microphones on another (in a closed room -- No-Go Zone for little brothers/sisters etc). :-)

The reason I haven't removed this statement long ago was that I thought I'd wait until we had a general article on compact audio cassette data storage in place, and then move the stuff over there, where it belongs (i.e., this technique was not limited to CBM Datassettes, but used across most home computer formats AFAIK). But thanks to your reminder, I'll 1) comment out the statement (using "<!--" and "-->"), and 2) a) start a compact cassette computer storage article myself, or b) expand the data storage coverage in the compact audio cassette article into a full section (if no one else beats me to it, that is). --Wernher 18:49, 1 Apr 2005 (UTC)

C2N vs 1530

Whilst they're functionally identical, the C2N name on its own seems to refer to the PET-style datassettes, whereas 1530 means the newer C64/VIC ones. Though this rule doesn't seem that firmly set, it seems to have been the common nomenclature.

In the datassette manual I have has the new-style drive on the cover, and refers to it exclusively as the "1530 DATASSETTE", but there's a note at the bottom of page 1 saying "This manual also applies to the C2N DATASSETTE". However, the same manual's cover reads:

1530 Datassette Unit
Operating Instructions
Model C2N

This survey, which presumably uses the nomenclature that Commodore users used, gives this breakdown of what datassette drive people own.

• 1530 datasette, 63.7%.
• C2N, 48.1%.
• 1531 (Plus/4), 15.1%. This alleges that there's quite a few 264-series computers connected to Datasettes.
• (Third-party clones, 26.1%.)

Crucially, it lists C2N and 1530 seperately. I have a original-shape datassette, and the label on its bottom calls it simply a "Commodore C2N Cassette", implying that the "Datassette" name came about later, presumably with the new-shape drives.

I propose that this naming distinction should be mentioned in the article. Can anyone who used 8-bit Commodores back in the day give any clarification, confirmation or objections? boffy_b 14:53, 24 August 2006 (UTC)

Commodore 1531-C64/128 compatibility?

The article says:

Through the use of an adaptor, [Commodore 1531] could be used with a C64/128, but only to read and write tapes in the 1531 format. As such, it could not be used to load C64/128 software.

I believe - in fact, I know - this is not true. I had a Commodore 64 and I used it with a 1531. (Bought by accident, as the store went out of 1530s.) 1531 had a Mini-DIN connector, so an adaptor was indeed necessary. But once you connected it, there was no difference: I could load games from my friends' 1530-recorded tapes without a problem, and they could load from mine. The format has nothing to do with the cassette recorder: it is determined by the computer that sends the data. GregorB 21:34, 21 September 2006 (UTC)

I apologise for putting this mis-information into the article. I bought a 1531 with an adaptor on ebay and tried to use it with my C64. Tapes would start playing, but not load, even though they worked with all other Datassette drives I have. I suppose either my adaptor or 1531 must be faulty. boffy_b 11:01, 11 October 2006 (UTC)

Well, no big deal - it's fixed now. Your problem may indeed be due to a hardware fault, but may also be due to the simple fact (not spelled out in the article, but rather well known) that - if turbo tape is used - the tape recorded on one 153x is not necessarily readable on another 153x without azimuth adjustment. So, when I said that I could load games "without a problem", that really meant "without a problem that azimuth adjustment could not solve". The article is also a bit unclear on one point: the device is indeed very unreliable, but that's only when turbo tape is used. Without turbo tape (i.e. working as designed) it is very realiable, but also slow to the point of being unusable. I'll update the article accordingly when I catch some time... GregorB 17:16, 11 October 2006 (UTC)

data format

Anybody has detailed information about the data format stored on tape?. Jcea 18:10, 6 March 2007 (UTC)

...and the (original) transfer rate? My guess is 512 bits per second, but I can't back it up with a citation. GregorB 15:24, 19 September 2007 (UTC)

http://www.zimmers.net/anonftp/pub/cbm/crossplatform/transfer/C2N232/ —Preceding unsigned comment added by Petchboo (talk • contribs) 18:04, 7 April 2008 (UTC)

“Turbo Tape” formats “only widely used in the UK”?

In its present version, the article makes a claim that so-called “turbo tape” software was “only widely used in the UK, as the US market had long since moved onto disks.” I think the “turbo tape” formats were widely used all over Europe – and at least in the Nordic countries. (I know for a fact that “turbo tape” loaders and storage formats were widely used in Finland – having used those utilities myself and seen them used commonly at the time.) — Jukka Aho (talk) 00:08, 19 April 2008 (UTC)

Reliable tape format? Reliable source?

I have taken umbrage to the repeated addition of this reference.

My reasoning is that the source itself is not reliable - it's a promotional brochure from commodore, so although I'm not saying it's bunkum, it should be taken with a critical eye.

Where is the comparison with other tape based systems to show that the C2n was indeed more reliable? At the moment, it's just an unsupported statement from the manufacturer of the drive system itself.

There is no secondary or tertiary source to agree with this article. I'll agree that the c2n may have been reliable - it it's speed it certainly should have been - but there is nothing to confirm that it was more reliable than any other format.

Incidentally, it's only the claim of being more reliable that I disagree with - I think the brochure itself is a great blast from the past, but I don't think it's good enough for a referenced source.

a_man_alone (talk) 18:05, 9 November 2010 (UTC)

I added a source from Compute's Gazette which states "Commodore's scheme for storing data on tape is quite complex-probably the most sophisticated used by any microcomputer manufacturer. The benefit of this complexity is that the system is extremely reliable. While users of other computers are frequently frustrated by programs that won't load properly from tape, many Commodore tape users never see a ?LOAD ERROR message. The disadvantage is that the complex system leads to long waits for programs to load." —Preceding unsigned comment added by Pantergraph (talk • contribs) 18:40, 9 November 2010 (UTC)

Thought about this, and still disagree. "Extremely reliable" does not equate to "most reliable", so I've changed the sentence. a_man_alone (talk) 22:06, 29 May 2011 (UTC)

In my own experience they were utterly unreliable as they seemed to be very sensitive to differences in the azimuth alignment and very often tapes from one unit could not be read by another unit. // Liftarn (talk)

your experience is not an encylopaedic reference — Preceding unsigned comment added by 24.89.139.58 (talk) 19:41, 30 August 2012 (UTC)

WP:COMPNOW applicability

Guy Macon (talk · contribs) and I disagree on a recent edit. I believe he is misinterpreting WP:COMPNOW in believing that it does not apply to the edit, and that the wording in Commodore PET he cites are examples of people making COMPNOW-violating edits, as opposed to supporting him.

"the Datasette uses a digital format" is correct, because "uses" is what COMPNOW describes as a static verb; nothing has happened since the days when the peripheral was contemporary technology to change how it works. Conversely, "The Datasette was more popular outside than inside the United States" is an example of a dynamic verb, because 25 years after the product's discontinuation it's no longer popular anywhere. Ylee (talk) 03:29, 10 January 2017 (UTC)

I am waiting to see if other editors have an opinion on this. --Guy Macon (talk) 11:02, 10 January 2017 (UTC)

I would support the use of present tense, based on the COMPNOW argument that there are still C2N units in existence, and that therefore the usage is still (or could be) current.

However, seeing as we're talking about this section, I do have an issue with the statement "Unlike most microcomputer storage methods using compact cassettes, the Datasette uses a digital format", and consider this to be misleading. "(W)riting two tones to tape to indicate bits" is still a digital format in that the tones represent ones and zeroes. There's a subtle difference between the data format (digital = ones and zeroes) and the way the data format is laid down to tape (digital square waves Vs analogue tones). Chaheel Riens (talk) 12:04, 10 January 2017 (UTC)

I am inclined to go along with whatever the consensus is here.

As for your other point, for reference, see http://www.zimmers.net/anonftp/pub/cbm/schematics/datassette/c2n.gif where it shows the write head being fed directly from two digital logic gates in push-pull configuration. Also note the DC erase head. That is certainly a digital format, but I I am not sure that the Kansas City standard used by other computers of the era would be considered a digital format. If I create a vinyl phonograph disk containing my voice speaking the words "one" and "zero" does that make vinyl phonograph disks a digital format? --Guy Macon (talk) 12:59, 10 January 2017 (UTC)

You're proving my point - you speaking "one" and "zero" is not a digital format, but you are using your voice to represent a digital data type, especially if those ones & zeroes are then used to represent binary data for use by a computer.

I'm not disputing digital-ness of the media, merely saying that it's misleading because there are two concepts being discussed - the format laid down to tape - digital in Commodore's case, and analogue in others - but also the actual data itself which regardless of the method is - to the common man - digital. Chaheel Riens (talk) 15:19, 10 January 2017 (UTC)

Recording system

@Guy Macon: I think we may have a terminology issue here, because by my reading, the recent revert you made is clearly at odds with the information already present in the page. Later in the article, there is a diagram of the pattern, which shows the signal as sine waves, and of two different frequencies. That the output from the computer is not identical to what is on the tape is pretty much the whole idea of cassette storage. So can you be more specific about what you think the problem here is? Because it looks like you are disagreeing with the content. Maury Markowitz (talk)

The image with the sine waves (which I believe was lifted from http://wav-prg.sourceforge.net/tape.html ) is bogus. That isn't how a Datassette works. As can clearly be seen on the schematics at ftp://www.zimmers.net/pub/cbm/schematics/datassette/index.html the signal going to the head is a digital square wave, not a sine wave as the image shows. (The actual signal on the tape is a distorted square wave as one would expect from an audio cassette being driven into saturation by a digital signal.) the statement "In the Datasette, instead of writing two tones to tape to indicate bits, patterns of square waves are used" is correct. The image is not. There are more details on this at [ http://c64tapes.org/dokuwiki/doku.php?id=analyzing_loaders ]

So the original claim ("In contrast, the Datasette has built-in analog to digital converters and audio filters to convert the computer's digital data into analog sound and vice versa") is wrong, and your latest edit ("In the Datasette, instead of writing two tones to tape to indicate bits, patterns of square waves are used including a parity bit.") is correct.

Related: [ https://retrocomputing.stackexchange.com/questions/143/what-format-is-used-for-apple-ii-cassette-tapes ]

--Guy Macon (talk) 16:42, 27 March 2018 (UTC)

"The actual signal on the tape is a distorted square wave " - this is what I was referring to, the Atari also outputs a square wave to tape but it is decidedly not square after writing. As to the diagram, it also shows two different frequencies. Is this simply a diagram from some other system? Maury Markowitz (talk) 11:06, 28 March 2018 (UTC)

It looks like it to me. This is an area where Wikipedia has trouble; a source ,makes a claim that anyone who understands electronics and can read a schematic can clearly see in wrong, but correcting it would be WP:OR. I looked for an actual oscilloscope image of the signal but could not find one. --Guy Macon (talk) 12:38, 28 March 2018 (UTC)

There used to be a duplicator that connected two datassettes without a C64 or VIC20. It used a TTL chip. --Guy Macon (talk) 12:38, 28 March 2018 (UTC)

If it's wrong, remove it. That's not OR. Maury Markowitz (talk) 13:52, 30 March 2018 (UTC)