Exactly. I did what you just said. Used the ground RXD TXD. And the examples shown online do not use the red wire(power line) at all. And that is exactly what i did. I went by the conventional method before starting to try out other things. also i later used the 3.3 V jumper. Do you have any suggestions on what i could perhaps try? Thanks
On Fri, May 20, 2016 at 11:49 AM, Harvey White <ma...@dragonworks.info> wrote: > On Fri, 20 May 2016 11:11:39 -0400, you 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) > > Even though you check after each try, putting a signal over 3.3 volts > on the BBB pins (or 1.8 volts on the analog pins) is just asking for > trouble. > > Good engineering says not to put too much voltage on processor pins. > > 5 volts on a 3.3 volt maximum pin is too much. You may or may not > have overstressed the pins, which may or may not fail sooner or later. > > If you are in college, and you have not been told this, then you need > to speak to your professors. Data sheet maximum ratings are not > suggestions. > > You need the ground and the RXD and TXD lines. The maximum voltage on > the RXD and TXD lines should be 3.3 volts, on the average adaptor, > there's a jumper for that. There's also a jumper to select a 5 volt > swing. You do not need either the 3.3 volt power line or the 5 volt > power line. > > Harvey > > > > > > >On Fri, May 20, 2016 at 10:32 AM, evilwulfie <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> > >>>> 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?utm_medium=email&utm_source=footer > > > >>>> https://groups.google.com/d/ > >>>> msgid/beagleboard/3b9db8f5-b454-4801-b4a5-49a867c0e255% > >>>> 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. > >> To view this discussion on the web visit > >> < > https://groups.google.com/d/msgid/beagleboard/30ad5a80-4c6b-453b-b74b-c63f010996c4%40googlegroups.com?utm_medium=email&utm_source=footer > > > >> > 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. > >> 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 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. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/ggbujb1tgbnopo5bgh2i32hu8ekd8l356c%404ax.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. 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