Cassettes and/or Interface

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Cassettes and/or Interface

After reading about Woz invented the disk ][ controller, (1978)
and used Shugart drives with them, why the Apple ][e
had cassette ports on the back on them as it was released
some time later. (1982)

Was it that people wanted to have access to both?
Or there was alot of software released on tape that was
not available on disk.

I never used cassettes, or the cassette interface, as
when I bought my ][e I bought a disk ][ controller and drive.

Or did the cassette port have other uses?

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Re: Cassettes and/or Interface

You can connect your IPhone and Load software:

http://asciiexpress.net/diskserver/

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Re: Cassettes and/or Interface

Allow me to respond to your question with a question. So when you bought your ][e with the controller and drive, you didn't already have a controller and drive lying around in the household?

I think you have to remember that back at that time, floppy equipment and media was expensive and new household data storage technology. By contrast, audio cassette was probably the most readily available read/write recording medium for households at that time, therefore it wasn't unreasonable to expect cassette players/records to already be present. Tape was the norm; still somewhat expensive, but not as much as floppy.

But you are probably also correct in that people wanted to have access to both. Who would want to buy a computer that couldn't read the information from their tapes written in the previous decade? Think of it as legacy support in the 1980's.

I don't know about other uses for the cassette port, but I would not be surprised if someone hadn't pursued this. If you think about it, at a very basic level you have a channel for data in and a channel for data out. Add some clever coding, PWM and a codec and there is potential for a simple data exchange system. A possible alternative use that I suppose might have or could potentially have been implemented through the cassette port would be something like a primitive MIDI interface - I have no idea whether it actually happened though.

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Re: Cassettes and/or Interface

Electric Duet has an option to output sound through the cassette interface.

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Re: Cassettes and/or Interface

I'm not an engineer, but I imagine there was very little that Apple would gain from removing the cassette jacks, except disgruntled legacy users. It was probably cheaper to continue including them.

The Apple //c (1984) and Apple //gs (1986) did away with the cassette jacks. However Apple continued to include them on all Apple //e models, including on the //e Platinum which sold between 1987 and 1993.

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Re: Cassettes and/or Interface

KF5SDR

That looks interesting about Electric Duet.
Will have to look at the program/manual to see how that works.

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Re: Cassettes and/or Interface

KF5SDR

That looks interesting about Electric Duet.
Will have to look at the program/manual to see how that works.

The Speaker is "Triggered" with I/O Port $C030..

The Cassette Out is "Triggered" with I/O Port $C020..

MarkO

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Re: Cassettes and/or Interface

from:
http://apple2history.org/history/ah13/

"Another of the earliest devices designed for the Apple II came from the Apple Pugetsound Program Library Exchange (A.P.P.L.E.). They were involved in distributing Integer BASIC programs on cassette to members of the group. To make it easier to send those programs to the person responsible for duplicating the cassette, Darrell Aldrich designed a means of sending the programs over the telephone lines. There were no modems available at the time, so his “Apple Box” was attached to the phone line with alligator clips and then plugged into the cassette port on the Apple II. To send a program, you first called up the person who was to receive it and got the computers on each end connected to the Apple Box. The sender then used the SAVE command in BASIC to tell the computer to save a program to tape. In actuality, the program was being “saved” through the cassette “out” port to the Apple Box, and onto the phone line connected. At the other end of that phone line, the data went into the other Apple Box, which was connected to the cassette “in” port on the other Apple II. That computer was executing the LOAD command in BASIC to “load” the program from the Apple Box. A.P.P.L.E. sold about twenty of these Apple Boxes at $10 apiece.[2]"

Also, audio could be sent out of the port. Overall it's very useful. Today you can load games, or bootstrap ProDOS without any additional hardware besides a PC or Phone to play the .wav.

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Re: Cassettes and/or Interface

Mark O

Of course it is! Apple II hardware is located
at $C000 - $C0FF (soft switches).
Thanks for the reminder.

I am interested in how the cassette port
was used as an early type of like OS.

Was software on tape encoded (RLL)?
Or was it just loaded straight on?

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Re: Cassettes and/or Interface

You should read the Woz PAC on how the Apple audio was encoded for cassette. It was a software scheme using digital to simulate an approximate analog signal while most vendors used an actual Modem type circuit.

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Re: Cassettes and/or Interface

I take it you are referring to WozPak.
I found The WozPak II on asimov
and there is no mention of it.

Is there a predecessor? (WozPak I)

Callapple have The WozPak special edition
which includes both I & II. This is only
available in book format. The reason not to
sell it as a PDF is to keep an authentic
book feel.

There is another publication Steve the Wonderbook.
The information on cassettes is for the Apple I.
It's hard to read as it is on his handwriting and
didn't do we'll when it was scanned. So still
nothing for the Apple ][ on cassettes.

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Re: Cassettes and/or Interface

Yes I meant wozpak. Teaches me to use my iPhone to write stuff in a rush and on the run.

But I think you are right, it's the wonder book. I always refer to both as the wozpak. It actually caused some confusion because I have an original wondebook that I brought to VCF east this year and I kept calling it a wozpack, though I knew better.

Anyway back on subject. The Apple II and Apple I basically have the same design for the cassette interface. There was just a minor change for in a cap value for reliability and the LED and related circuitry was dropped. The circuit is so similar that Mike Willegal's brain board can use the Apple II interface to read Apple-1 cassettes.

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Re: Cassettes and/or Interface

Wasn't even looking for this but
found some information about cassette
encoding. (The Internet is strange that way)
An interesting read.

The link is below

http://www.fadden.com/apple2/cassette-protect.html

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