Under Windows 7, Qt 5.3 I have problems to set the baudrate of a QSerialPort: @QSerialPort *serial = new QSerialPort(this); serial->open(QIODevice::ReadWrite); serial->setBaudRate(115200);@ setBaudRate returns true, but on some machines the baudrate is no. It seems that custom baud rate feature. 921600 baudrate is not set QSerialPort on Mac OS X 10.9: 921600.

I know 9600, 19200, 38400, 57600, 115200 and 1.8432 Mbaud, but no others. Why are these values used, and is it simply doubling each time or is there something more complex going on (for example, 38400 quadrupled is not 115200 baud?) The reason I ask this question is I'm designing something which may have to interact with a variety of different baud rates. It will initialise in 9600, and then switch to a specific baud rate. But I can't support arbitrary rates because the dsPIC33F I am using does not support arbitrary rates as it is limited to a 16-bit BRG down counter. It's similar in this regard to many other processors. It started a long long time ago with teletypes - I think 75 baud. Then it's been mostly doubling ever sice, with a few fractional (x1.5) mutiples, for example 28800, where there were constraints on phone-line modem tech that didn't quite allow it to double. Nagin song tamil serials free download audio.

Standard crystal values came from these early baudrates, and their availability dictates future rates. 7.3728 MHz / 16 = 460800 baud, 7.3728 MHz / 64 = 115200 baud. Most UARTS use a clock of 2^n x16 of the baudrate, more modern parts (e.g.

NXP LPC) have fractional dividers to get a wider range by using non-binary multiples. Other common standards are 31250 (MIDI) and 250K (DMX), both likely chosen as nice multiples of 'round' clocks like 1MHz etc. I refurbished two year 1926 teletypes, back in college (1976) and yes they ran at about 75 baud. They were labeled baudot teletypes. Plugged into 110vac and a motor provided the timing, with electrical connection between them.

I dunked them in gasoline to clean them. (Give me a break -- I was 18. But it worked!) Ctrl-G rang an honest to goodness bell at the other. Alas, I don't even remember who I gave them away to.:-( So, yeah, you'd type on the mechanical keyboard, it would mechanically serialize your keystrokes, and make-and-break a contact which the other side read. – Jan 23 '17 at 22:17 •. RealTerm, a freeware Windows terminal program, lists these UART rates in its Baud menu: 110, 150, 300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600 However these are actually bits per second (bps), not baud -- see below. 110 baud was used by 8-level Teletypes like the ASR-33.

I'm not aware where 150 Baud was used, but it is a doubling of 75 baud, commonly used (along with 60 baud) for 5-level TTYs. 300 bps was the standard for the first widely-used telephone modems in the 1960's. A number of 30 character per second terminals appeared at the same time. Above 300 bps/300 baud, which used simple frequency shift keying (FSK), the figures for bps and baud (symbols or tones per second) are not the same. For example, a 1200 bps modem actually runs at 600 baud, and a 4800 bps modem runs at 1600 baud. Refer to the table under Bandwidths in this.

Adriana antoni iubirea mea download zippy florin. The difference is because in addition to using a certain number of tone pulses per second, phase-shift keying and are used to extract additional bandwidth from the same baud rate to get higher and higher bps. (So a 56K modem is actually only running at 8000 baud.) As you can see, the list of UART rates essentially started at 75 and continually doubled (skipping 600), until getting to 38400, where it was multiplied by 1.5 to get 57600. 56K bps is the limit for an analog telephone line.