[Coco] The early (and dark) days of sending data.
Steve Bjork
6809er at bjork-huffman.net
Sun Apr 12 11:33:38 EDT 2009
Roger,
While ASCII streams did allow manual entry, I nor anyone that I knew
back than ever encoded a file by hand.
There was always a program around to encoded it, even in the early 70's.
By the way, a side effect of 110 baud speed was the delay in how long it
would take for the teletype terminal to print what you were keying in.
It would take about 200 milliseconds (1/5th of a second) to send the
character to the mainframe and send it it back to print it.
I could never get over the delay of hitting a key and the pause before I
heard it imprint on the paper.
Oh yes, the teletype also had its own delay while it lined up the right
character to print.
After stepping up to CRT terminal at 9600 baud, you could never go back.
Yes, those were the days. Dark days. But technology move on.
Steve Bjork
Roger Taylor wrote:
> At 10:24 PM 4/11/2009, you wrote:
>> Brian, all attachments for email are larger than the file sent
>> because they are encoded ASCII and not in binary format.
>> It's a hold over from the 7-bit format days of early modems and
>> pre-Internet.
>>
>> Remember, sending a 7-bit character was 9% faster than sending full
>> 8-bit character.
>>
>> An old 500 8-bit character message sent at 110 baud would take 50
>> seconds.
>> But a 500 7-bit character message send at the same speed would only
>> take 45 seconds. (5 seconds faster.)
>>
>> The extra bit was a big deal till modem speeds hit about 2400 baud or
>> so. But it was too late because encoded ASCII was the standard for
>> attachments.
> ASCII streams also allow for manual entry and EOL termination by
> keyboard.
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