USB to Serial adaptor

Robin

I have a PC with both serial ports and USB ports.· I am using a USB-Serial adaptor to use my Parallax servo controller on my USB port.· With the USB to serial adaptor installed, can I still use my serial ports normally to communicate with my BS2?· I have hooked my oscilloscope up to my serial port and send out a digit and what I get on my scope·is not RS-232.· Is this because of the USB-Serial adaptor software or something else?

Mike Green

Yes, you can use both the USB-Serial adapter and the normal serial port at the same time. As far as the PC software is concerned, they're equivalent.

If you have a serial port on the PC, it has to be RS232. Are you looking at the transmit / ground lines? Some PC serial ports are not quite standard, particularly some laptops. What are you actually seeing?

Robin

I am seeing about 32 bits and I can't pick out the actual bits for the character I am sending, eg. "1" or "k".· I think there should be only 8 data bits shouldn't there?· Doesn't make any sense to me.

Robin

I am using the transmit and ground lines only.

Thanks

pwillard

en.wikipedia.org/wiki/File:Rs232_oscilloscope_trace.svg

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There's nothing like a new idea and a warm soldering iron.

stamptrol

Unless you can identifiy the Start bit reliably, the 8 data bits may get confused (on the 'scope) with the parity bit and any stop bits and/or the succeeding Start bit.

I'd setup a test so you know good data is flowing between two devices (stamp-Stamp or computer to stamp) then hook up the scope. Don't forget real rs-232 voltage levels are "upside down".

cheers,

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Tom Sisk

http://www.siskconsult.com
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