USB I/O via R
Hello, Do you know Python programming language ? If yes, you can consider these packages : RS232 / USB acquisition python library : http://pyvisa.sourceforge.net And the robust Python interface to the R programming language : Rpy , http://rpy.sourceforge.net You can acquire data and regularly send vector to R using Rpy. My two cents, Bests regards, C.
On 24 jan, 03:01, Atul Sharma <atul.sha... at mcgill.ca> wrote:
I have an ongoing need to read a real-time data stream via the USB ? port on a MacBook Pro (OS 10.5.6). I have several different hardware ? sources, including commercial rs-232 instruments and a number of ? microcontrollers, such as the Atmega168 ?or Hitachi H8, but my ? question is generic to any serial I/O device, I think. To date, I have ? been content to interact with the microcontroller via terminal.app, ? where the 'screen' function allows me to exchange data with the card ? and to capture the incoming ASCII text stream to disk. From within R, ? this ASCII data file is then read and processed. Since it is independent of the R read.table() command, ?I'm sure it ? has to do with the details of the 'screen' implementatation or OS time- sharing. The problem is that the data appears to be written to disk at ? irregular ?intervals, and it lags what is actually being received/ displayed by 2-3 seconds. While this has not been a problem to date, I ? will soon need more "real time" access to the serial port, and I was ? wondering if there was a way to access it directly from within R i.e. ? a serial port communications library for R. Simple ASCII text read- write is all I require. ?I have not had any luck with attempts to ? search this group and google for ?"serial", "rs-232", "usb"," i/o" ? etc, but ?I was wondering if any one has any experience they'd be ? willing to share with inputting serial port data directly into R on ? the Mac?