Start bit in a RS-232 communication

chachicool · September 2009

Hi!, I am trying to control a device which protocol says: "19200 baud, 1START BIT, 8 data bits and 1 stop bit with LSB first". This is the first time that i see this 1 start bit and as far as i know it's possible to establish different number of stop bits but nothing referring to that 'start bit'.

That is the default RS-232 configuration(1 start bit) or is it necessary to change something??

Thanks in advance

DHawthorne · September 2009

Ancient terminal protocol uses $02 as a start bit, and $03 as an end bit. Many modern protocols carry this tradition on, but it is by no means universal, and could be nearly anything. Try that, and if it doesn't work, you will have to find out how they define it. Marantz made me crazy back in the beginning because they had two seperate documents - one detailing the command sets, and another on the packet structure; so it may require some research.

If you name the device for us, someone may know.

AMXJeff · September 2009

one start bit is normal, no need to do anything...

chachicool · September 2009

Thanks for the quick response!!

Start bit in a RS-232 communication

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