Clarence Verge <[EMAIL PROTECTED]> wrote:
>Bernie wrote:
>>
>> Baud is, and always will be, AFAIK the frequency inside the modem (which
is
>> changed with regards to frequency and amplitude to get the higher speeds
>> (anything above 2400 bps IIRC)).
>
>Baud (short for baudot) has nothing to do with the modem.
>The normal teletype baud rate is (was) 110 baud. (No modem)
>
>The serial transmission rate is neither just DATA bits or DATA bytes per
>second due to the overhead of one start bit and at least one stop bit.
>But in the case of the teletype that's two stop bits and in other cases it
>can be almost any silly number you want, <G>
>
>So, to transmit a BYTE of teletype data you must send 11 bits.
>If you specify BAUDrate then supposedly the reader will know what
>arithmetic
>is required to get the BYTErate.
>To get the byte rate, divide baud by the #bits/char.
>
>33.6Kbaud is 33600/10 bytes per second. (Compression not considered)
>
>- Clarence Verge
Clarence -
Sorry to have to contradict you, but I feel I must.
Baud and BPS (Bits Per Second) are NOT the same, nor even equivalent, any
more. Here is the definition I used in the "Telecommunications Basics" class I
once taught:
Baud - A measurement of the signaling speed of a data transmission device;
equivalent to the maximum number of signaling elements, or symbols, per second
that are generated; may be different from bit rate, especially at higher
speeds, as several bits may be encoded per symbol, or baud, with advanced
encoding techniques such as phase-shift keying, trellis-coding, etc.
Basicly, for any modem faster than 600BPS, baud <> bps.
Baudot Code - The original teletype data transmission code invented by the
Frenchman Emile Baudot. Implemented about 1870, it was composed of marks and
spaces so named because of the practice of punching marks into a paper tape.
Baudot uses five bits for character representation, one of which is a
letters/figures shift. Only upper case letters are used. Transmission was
asynchronous and originally accomplished by reversing the polarity of the DC
telegraph line. By the 1920s FSK modulation was used. In Telegraphy, Baudot
code was replaced by ASCII in the late 1960s.
Dave
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