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- Newsgroups: comp.sys.ibm.pc.misc
- Path: sparky!uunet!ftpbox!motsrd!white!rtsg.mot.com!catfish11!yedinak
- From: yedinak@rtsg.mot.com (Mark A. Yedinak)
- Subject: Re: Q: Are the Baud Rate and BPS same?
- Message-ID: <yedinak.716594077@catfish11>
- Sender: news@rtsg.mot.com
- Nntp-Posting-Host: catfish11
- Organization: Motorola Inc., Cellular Infrastructure Group
- References: <1992Aug28.155701.218@news2.cis.umn.edu> <1001@engcon.marshall.ltv.com>
- Distribution: usa
- Date: Tue, 15 Sep 1992 21:54:37 GMT
- Lines: 47
-
- fenner@engcon.marshall.ltv.com (JWFENNER) writes:
-
- :Baud rate and Bits per second are essentially the same thing.
- :For example, if you have a 2400 baud modem, you can transfer
- :2400 bits per second. Bytes per second is another story, however.
- :Data sent over the modems is broken down as follows:
-
-
- The above is really true. The baud rate describes the line characteristics.
- It represents the number of oscillations per second of the signal. Bits per
- second is exactly that, the number of bits per second which are transmitted.
- It is true that most low baud modems, the bps is the same as the baud rate.
- However there are many techinques which can be used to send multiple bits per
- each oscillation of the line. Therefore, the bps is not equal to the baud
- rate.
-
- It is always best to use the two terms independently. The baud rate simply
- describes the the line characteristics while the bits per second describe the
- transfer rate of the data. What is being described by the two terms is not the
- same thing and should not be confused with each other.
-
- :+-----------+-----------+-------------+
- :| START BIT | DATA BITS | STOP BIT(S) |
- :+-----------+-----------+-------------+
-
- :where START BIT is 1 bit, DATA BITS is generally 8 bits (without parity),
- :and STOP BITS is usually 1 bit. These numbers can vary, but this is the
- :most common format used today.
-
- :What this means is that for each BYTE of data you send, you actually send
- :10 bits, not just 8. So your effective BYTES PER SECOND would be 240 for
- :a 2400 baud modem.
-
- This is basically correct.
-
- :Most of the newer modems also use compression techniques to help improve
- :the EFFECTIVE baud rate.
-
- Again, the baud rate only defines the characteristics of the line, not the
- transfer rate of data on the line. There is no such thing as an effective baud
- rate, only an effective data rate.
-
- --
- Mark A. Yedinak - yedinak@rtsg.mot.com * "Don't take life too
- Motorola - Wireless Enterprise Systems * seriously, you will
- 3205 Wilke Road, Arlington Heights, IL 60004 * never get out of it
- 708-632-2874 (I said it, not the big M) * ALIVE!"
-