minimum baud rate nrf52832

Question

Dears, what is the minimum baud rate of nrf52832? Can I achieve 1200 or 600 bps? if so, how this can be set up?

StanislavDimitrov · Accepted Answer

So by playing with the clock speed or low-level counters, less than 1200 bps cannot be achieved?

hmolesworth · Answer

I disagree; many baud rates are possible, try playing with this:

// Baudrate generator for the UART is the top 20 bits of a 32-bit field; add in rounding 0.5 ls bit
 uint32_t RequiredBaudRate = 600; // whatever ..
 uint32_t CalculatedRegisterValue;
 uint64_t SystemClock = 16000000ULL;    // Typically 16MHz
 uint64_t MagicScaler = 32; // Preserves bits on divisions, shift 32 bits
 CalculatedRegisterValue = (uint32_t)(((((uint64_t)RequiredBaudRate << MagicScaler) + (SystemClock>>1)) / SystemClock) + 0x800) & 0xFFFFF000;

Did you know that with a screened twisted-pair cable using RS485 (easy on nRF52) it is possible to transmit a distance of 4 miles at 1200 baud or less? Don't ask, once I had to do just that ...

minimum baud rate nrf52832

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