FTDI with 250K baud

Development Boards Arduino
1

i am trying to have my arduino send serial data at a baud rate of 250K.

but my mac osx does not have 250K as one of it’s standard baud rates.

i read about aliasing baud rates which is done by altering System/Library/Extensions/FTDIUSBSerialDriver.kext

http://www.dbpharrison.com/general/thermitrackdriver/

ftdi has also talks about this in it’s manual:

http://www.ftdichip.com/Support/Documen … Driver.pdf

but i am not sure which of the many listed device to change.

any advice?

thanks.

2

the Arduino’s UART and crystal frequency likely cannot run at 115200, nor higher. To run at these speeds, a crystal of 14.7456MHz is needed. Even so, higher than 115200 is unlikely.

Also, it may be that some of Arduino libraries are hard-coded for other than 14.7456MHz.

3

so far it is not a problem to receive data at the arduino from my computer at 250K.

i followed this tutorial and it works great

http://playground.arduino.cc//DMX/Ardmx

my setup is computer - enttect dmx device - rs485 chip - arduino. and it works.

but now i also want to send data back to my computer and don’t want to/ don’t know how to send it back through the same dmx device. so i thought to send it back through a sparkfun rs485 to usb adapter.

a work around would be to figure out how to send and receive at different speeds. for example tx at 9600 and rx at 250K