30 Jan
2023
30 Jan
'23
10:47 a.m.
On 1/30/2023 11:14 AM, Chris via cctalk wrote:
> It had a dedicated cassette port? Don't most cassette ports resemble a
> serial port, or is my wonky brain making that up? What protocols did most
> cassette ports use (c64/128?, IBM 5150, coco ...)?
On Mon, 30 Jan 2023, Jim Brain via cctalk wrote:
Lots of systems had dedicated cassette ports, but yes,
CoCo has a dedicated
cassette port, as does all the 8 bit CBM machines, I think the Model 1/3/4
also, and doesn't the Apple II have one as well. I am sure I am forgetting
a bunch.
The 5150 had a cassette port!
Diagnostics were supplied on cassette tape.
It was immediately adjacent to the keyboard port, and used the same
5 pin DIN connector, for the added convenience of being able to plug in to
the wrong one. THAT mimiced the TRS80 model one, which had Power, video, and
cassette in a group of three 5 pin DIN identical connectors.
THAT, and the keyboards of the Jr and Coco, were to show that IBM was so
big that it didn't have to learn from the misteaks of others.
Since the 5150 cassette connector was the same 5 pin DIN as
the TRS80, the source of cable for 5150 cassette was Radio Shack TRS80
cassette cable.
There was an outfit that marketed a sorta network using the 5150 cassette
port, for classroom distribution, etc.
Adding 160K (and/or 180K,320K,360K with DOS 1.10 and 2.00) required the
floppy disk controller board for about $300, DOS, and standard SA400
interface drives (such as borrowing from your TRS80); power connectors
were already built in. So, few ever used the cassette port.
It was months before after-market "multi-function" boards were available,
so a 5150 consisted of main unit (~$1250), FDC (~$300), video board
(~$300), monitor (CGA had compoosite output, so could connect to cheap
CCTV, etc. monitors, and CGA even had a dedicated 4 pin Berg for the
SupRMod RF adapter), and maybe serial, and/or parallel.
The 5160 no longer had the cassette port.
The 5150 cassette sorta network immediately disappeared from the market.
--
Grumpy Ol' Fred cisin(a)xenosoft.com