What is not a standard windows UART baud rate?
- 150 Baud
- 300 Baud
- 55 Baud
- 110 baud
EXPLANATION
It started a long long time ago with teletypes — I think 75 baud. Then it's been mostly doubling ever since, with a few fractional (x1.5) multiples, for example 28,800, where there were constraints on phone-line modem tech that didn't quite allow it to double. Standard crystal values came from these early baudrates, and their availability dictates future rates. E.g.,Most UARTS use a clock of
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 31,250 (MIDI) and 250K (DMX), both likely chosen as nice multiples of 'round' clocks like 1MHz etc.
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