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[on:]

i know how to use the "serial.begin" feature, but i'm just curious, if the baud rate is essentially the bits per second, why is it baud and not bps? (it's not that baud isn't fun to say, i'm just curious)

[Reply #1 on:]

http://www.pccompci.com/Baud_Rate.html

Named after J. M. Emile Baudot (1845-1903), who was a French telegraph operator, who worked out a five-level code (five bits per character) for telegraphs? It was standardized as International Telegraph Alphabet Number 2, and is commonly called Baudot (and is a predecessor to ASCII). Since 2^5 is only 32 and the uppercase letters, numbers, and a few punctuation characters add to more than that, Baudot uses Shift In and Shift Out characters (analogous to how the Caps Lock key on a PC keyboard reduces the number of keys needed by enabling each letter key to represent two characters).

[Reply #2 on:]

Baud rate tells you how often to read the signal you're sent. That signal may convey several bits of information. In the case of arduino serial comms, it only gives a single bit, so baud and bps are the same. In a more sophisticated transport, that may not be the case.

http://en.wikipedia.org/wiki/Baud

[Reply #3 on:]

ah! thanks for the speedy replies! i was thinking that baud was an awfully strange acronym

[Reply #4 on:]

I saw one of those oval stickers on a car the other day that said 19.2 and the first thing that popped into my mind was "baud rate". You see 26.2, 13.1 etc. for marathoners and half-marathoners but I never did figure that one out, could not convert it to any recognizable standard mile or kilometer value.

[Reply #5 on:]

We use bps (bits per second) and kbps a lot.  Baud is easier to say and more understood than 'bips'.

[Reply #6 on:]

Wikipedia.
Google.

[Reply #7 on:]

Wikipedia.
Google.

We appear to have reached the stage where 'googling for information' has been replaced by 'get someone else to google for information'.

[Reply #8 on:]

Wikipedia.
Google.

Funny as it may seem, that's becoming a common answer in everyday casual conversations too... :-)

[Reply #9 on:]

People not wanting to look something up is new?

[Reply #10 on:]

I think it is, I will go and look it up. 

[Reply #11 on:]

LOL, when I was a kid I knew lots of adults who wouldn't even look up spelling (let lone meaning!) in a dictionary!
Nothing new at all, once the -majority- got past high school (or quit) those days were over for them.

[Reply #12 on:]

You see 26.2, 13.1 etc. for marathoners and half-marathoners but I never did figure that one out, could not convert it to any recognizable standard mile or kilometer value.

My first idea it represents time, thinking twice it could be (1) time for 5 or 10 KM   (2) the marathon time - 2hours?  or (3) are these just random numbers to keep nerds busy?

[Reply #13 on:]

We use bps (bits per second) and kbps a lot.  Baud is easier to say and more understood than 'bips'.

Of course baud has often been abused as meaning bits/s when it doesn't... Baud is defined relative to some set of symbols used for signalling (for instance if QAM modulation it might be as many as 64 symbols, so that the baud rate is 1/6th the bit rate).

[Reply #14 on:]

Yes the baud rate is the DATA RATE, this is sometimes equal to the bit rate but not always.

QAM - Quadrature Amplitude Modulation - a system where by at any one instant the state of the signal is not a simple logic HIGH and LOW but can have one of many possible states. There are many types of QAM, the simplest just have four states denoted by a phase shift in the signal. There are four such states hence the quadrature in the name. So a signal can have a phase shift of 0, 90 180 or 270 degrees. So such a signal carries two bits of information for each state it is in. The bit rate is how fast the state changes but the Baud rate is how much information is transmitted. So here the Baud rate is twice the bit rate.