the output from the bbb is 3.3v not 5v. if you use anything other than some kind of level translator you risk harming your BBB
it talks about that in the BBB srm. On 5/20/2016 8:17 AM, Shaurabh Kumar Singh wrote: > Do you guys think i should also try a FTDI USB to Serial Adapter for > BBB? It might eliminate the voltage issue altogether. > > On Fri, May 20, 2016 at 11:14 AM, Shaurabh Kumar Singh > <ssing...@ncsu.edu <mailto:ssing...@ncsu.edu>> wrote: > > CTS and DTR were not activated at the PC interface, i had looked > up the serial port settings on which it was working. Anyway i did > try with and without both and individually as wel. > > On Fri, May 20, 2016 at 11:11 AM, Shaurabh Kumar Singh > <ssing...@ncsu.edu <mailto:ssing...@ncsu.edu>> wrote: > > The RX and TX at the beaglebone are working just fine. The TX > output from the RS-232 is 5V. Also i tried with and without > connecting the red wire(5V) from the RS 232. The necessary > connections are GND (black wire) , RX and TX(green and white > wires) of the PL2303 USB to Serial adapter. > I also tried using a BeagleBone Black RS-232 Serial Micro-cape > (see http://www.logicsupply.com/cbb-ttl-232/). > > Note: RX and TX are working just fine for all the UART > ports.(i confirm after every try) > > On Fri, May 20, 2016 at 10:32 AM, evilwulfie > <evilwul...@gmail.com <mailto:evilwul...@gmail.com>> wrote: > > if he connected it to the cnc with no 3.3v adapter it also > could have fried the bbb. > > > > > > On 5/20/2016 7:08 AM, Wally Bkg wrote: >> >> You do realize that on your PC the RS232 signal levels >> from the COM ports are +/- 12V while without extra >> hardware the Beaglebone levels are 0-3.3V? You may have >> fried the RX input on the Beaglebone if you've connected >> it directly to a +/- 12V RS232 TX output. >> >> Assuming you've got the logic levels right, If you used a >> "standard" serial cable on your PC to the CNC machine it >> probably activated the CTS or DTR automatically, you may >> need to run one more wire from the Beaglebone, or tie it >> active on the CNC interface side. >> >> >> On Friday, May 20, 2016 at 7:36:15 AM UTC-5, Shaurabh >> Kumar Singh wrote: >> >> The cnc is dte as far as I know. >> And I am assuming since it worked without hardware >> handshaking on my pc, it shouldn require the same for >> the bbb either. >> That said, I have tried both the settings. With and >> without hardware handshaking. >> The only thing I can think of is for some reason >> perhaps, the default serial port settings must be >> different on the bbb (with debian) than my pc (where >> I previously successfully had communicated-windows) >> >> On 20 May 2016 08:19, "Wally Bkg" >> <wb666...@gmail.com> wrote: >> >> On Thursday, May 19, 2016 at 7:08:55 PM UTC-5, >> Shaurabh Kumar Singh wrote: >> >> Okay. I shall look it up. >> By the way, i did confirm the working of the >> UART pins(UART1 RX to UART4 TX and vice versa). >> I had two terminal tabs open and when i typed >> into one and entered(UART1 settings) it >> showed up on the other terminal with UART4 >> settings. I inferred that the Adafruit >> libraries work just fine for the BBB (correct >> me if i am mistaken) >> >> It is just that while interacting with a CNC >> machine(with a HAAS OS) it is not >> communicating rather just showing up what is >> being sent. >> >> >> You may need CTS or DTR active for the other end >> to accept data and respond. Are you sure the CNC >> machine doesn't need a "hardware handshaking" >> protocol? >> >> If you have uart1 talking to uart4 on the >> Beaglebone, that says the problem is the physical >> connection and/or the protocol to the CNC >> machine. Is the CNC machine wired to be DTE or DCE? >> >> At this point I think you need help from the CNC >> machine's documentation, or from >> someone familiar with that particular machine. >> >> -- >> For more options, visit >> http://beagleboard.org/discuss >> --- >> You received this message because you are >> subscribed to a topic in the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this topic, visit >> >> https://groups.google.com/d/topic/beagleboard/Z1s_NwXYNrw/unsubscribe. >> To unsubscribe from this group and all its >> topics, send an email to >> beagleboard...@googlegroups.com. >> To view this discussion on the web visit >> >> https://groups.google.com/d/msgid/beagleboard/3b9db8f5-b454-4801-b4a5-49a867c0e255%40googlegroups.com >> <http://40googlegroups.com>. >> For more options, visit >> https://groups.google.com/d/optout. >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to >> the Google Groups "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails >> from it, send an email to >> beagleboard+unsubscr...@googlegroups.com >> <mailto:beagleboard+unsubscr...@googlegroups.com>. >> To view this discussion on the web visit >> >> https://groups.google.com/d/msgid/beagleboard/30ad5a80-4c6b-453b-b74b-c63f010996c4%40googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a > topic in the Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > > https://groups.google.com/d/topic/beagleboard/Z1s_NwXYNrw/unsubscribe. > To unsubscribe from this group and all its topics, send an > email to beagleboard+unsubscr...@googlegroups.com > <mailto:beagleboard+unsubscr...@googlegroups.com>. > To view this discussion on the web visit > > https://groups.google.com/d/msgid/beagleboard/0eb51074-b51a-f658-f69c-10a7ec8aa58b%40gmail.com > > <https://groups.google.com/d/msgid/beagleboard/0eb51074-b51a-f658-f69c-10a7ec8aa58b%40gmail.com?utm_medium=email&utm_source=footer>. > > > For more options, visit https://groups.google.com/d/optout. > > > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google > Groups "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to beagleboard+unsubscr...@googlegroups.com > <mailto:beagleboard+unsubscr...@googlegroups.com>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/CAEh-rEEM3gnROWQSsFiVEEqtk5x%2BFVXTFtq%2BhUEh7n4nU_eT-g%40mail.gmail.com > <https://groups.google.com/d/msgid/beagleboard/CAEh-rEEM3gnROWQSsFiVEEqtk5x%2BFVXTFtq%2BhUEh7n4nU_eT-g%40mail.gmail.com?utm_medium=email&utm_source=footer>. > For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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