On Sunday 03 March 2019 01:22:51 Thaddeus Waldner wrote: > Maybe there was not so much dweeb in the Toshiba marketing department > as there was ignorance in the hobbyist integrator.... > > It turns out they don’t call the port an RS485 port; they call it a > Toshiba Inverter Protocol port. They sell converters that converts the > Toshiba port to either RS232 or RS485. These cost about $130 on ebay, > which I don’t necessarily want to spend. I found this; > http://static.mah.priv.at/cnc/vfs11-rs232.pdf > > Can you or anyone enlighten me as to what is taking place with the > Schmitt trigger inverter and MAX232 chips? The the toshiba protocol > does not appear to use differential signals. > A Schmitt trigger is a chip that doesn't have a middle trigger voltage, but a higher on voltage and a lower level logic zero output, commonly used as a noise filter because it ignores up to a volt of random noise. The max232 is a level translator designed to to pump a 5 volt "ttl" logic signal up to a + or - 12volt swing to feed a serial data train up to the voltages commonly used for rs232 communications.
They may want $130 for it, but that little pcb actually contains maybe $6 in parts. Looks like a db9 connector is used at one end and a card edge must be assumed at the bottom of that drawing, probably plugging into a card edge socket in the vfd. And you would talk to the vfd, in all likelyhood using the std 7 wire flow protocol, built into most any pc with a seriel port. Those are vanishing critters though so you may have to use a usb to serial converter at the pc end. To a C.E.T., and I am one, there's no magic in that circuit, its simply makeing an rs232 compatible signal for the db9 from a ttl level signal and doing it bidirectionally. Take a look on ebay and if you recognize the jargon, you can get a bag of 10 of them for less than a $20 bill. 6+ weeks for delivery from China though. You need a "ttl to rs232 convertor", and you'll probably need to adapt the lower end of it to the socket it connects to in the vfd. That 24 volts you found could be 5 volts, but 24 is what the vfd supplies. So you may have to add that 7805 regulator thats makeing 5 volts for the rest of this convertor from the 24 the vfd supplies. That could be on the card edge adaptor you'll have to make. Whose interfacing card are you going to use? Some of the mesa stuff has all those signals shown hitting the db9 on terminal connectors, bypassing the need for the db9 connector, you just strip the wire, stick it into the terminal and tighten the screw. > Thaddeus Waldner > ________________________________ > From: Gene Heskett <[email protected]> > Sent: Saturday, March 2, 2019 5:31 PM > To: [email protected] > Subject: Re: [Emc-users] VFS-11 modbus driver > > On Saturday 02 March 2019 17:47:26 Thaddeus Waldner wrote: > > I get 24v on one wire, zero on all of the rest. > > Thats not a legal voltage on any pin of an rs485 connection. Some > marketing dweeb is playing fast and loose with the jargon IMO. > > Its (rs485) a balanced differential signal where one wire is compared > to the other to determine the logic state. Because most noise is > longitudinal, meaning its identical on both wires, comparing two noisy > wires is a good way to get extreme noise immunity. I haven't > personally used the circuit for that, but I made the mistake of buying > an encoder with differential outputs on 6 wires. Feeding that encoder > a/b to a pair of diff to ttl gismo's sold as an rs485 interface you > can get for about a dollar a copy on ebay, I made perfect ttl signals > out of that encoder at close to a 100 kilohertz. fed as single ended > to an encoder in a mesa 5i25, linuxcnc loved it. I think that it was > intended to run on 12 volts, but its happy as a clam on 5 volts and > has been for a year now. The actual signal wires are sitting at about > 2 volts, have about a 200 mv signal on each wire from the omron > encoder. I had to wire them up as one way, though they can be full > duplex on those 2 wires. Someone else with wider experience than I > might be able to help. All my experience with vfd's has been with > direct controls, not all of which has worked. > > > Thaddeus Waldner > > Newdale School > > Elkton, SD 57026 > > > > ________________________________ > > From: Gene Heskett <[email protected]> > > Sent: Saturday, March 2, 2019 8:48 AM > > To: [email protected] > > Subject: Re: [Emc-users] VFS-11 modbus driver > > > > On Saturday 02 March 2019 08:31:57 Thaddeus Waldner wrote: > > > I purchased a usb RS485 port that looks similar to the one you > > > have. I have the VF-s11 driver successfully loading and exposing > > > its HAL pins. The HAL pins are connected and are switching with my > > > spindle start-stop commands. I have also set the baud rate, > > > parity, number of bits, stop bits, and target where applicable in > > > both the .ini file and on the inverter panel. > > > > > > And I get nothing. > > > > > > I wonder if i’m not missing something. I do have an actual VF-S9 > > > instead of the VF-s11, but the VF-s11 documentation states that > > > the I/O should mostly match. > > > > > > I suspect that maybe I am using the wrong pair of wires on the > > > RJ45 connector. I couldn’t find any Toshiba documentation on that > > > so I just used what appears to be a standard for RS485 half-duplex > > > on that connector; the blue = A and the blue-white = B. > > > > First, find a ground on the vfd, then you should see a low voltage, > > maybe 2 volts or thereabouts on the active wires used. The other 6 > > s/b millivolts or less. you may have to interchange them to get the > > correct polarity. Whoever thought useing an rj45 for a 2 wire > > circuit ought to be fixed so he can't make any more such mistakes. > > Sure its cheap, and dependable but theres also 7!=49 ways to screw > > it up! > > > > > The manual indicates that the inverter is always listening for > > > serial communication, and that sending the inverter enable signal > > > automatically cedes control from the inverter panel to serial. For > > > this reason I assume that I don’t need to enable serial > > > communication on the inverter in order for it to work. > > > > > > Thaddeus Waldner > > > ________________________________ > > > From: andy pugh <[email protected]> > > > Sent: Tuesday, January 29, 2019 4:07 AM > > > To: Enhanced Machine Controller (EMC) > > > Subject: Re: [Emc-users] VFS-11 modbus driver > > > > > > On Tue, 29 Jan 2019 at 01:39, Thaddeus Waldner > > > <[email protected]> wrote: > > > > > > As I understand it, I need a RS485 port. Is it reasonably possible > > > to add a > > > > > > > second serial port on some of the unused I/O pins to the MESA > > > > card? Would I be better served buying a usb-RS485 adapter? > > > > > > The vfs11 driver runs in user-space so the fact that you can't > > > have realtime control through USB is not such a problem. This > > > means that a cheap USB-RS485 dongle probably is as good a way to > > > do it as any. This is how I connected my VFD. > > > https://forum.linuxcnc.org/forum/18-computer/30675-on-motherboard- > > >mo db us-rs485-connection > > > > > > -- > > > atp > > > "A motorcycle is a bicycle with a pandemonium attachment and is > > > designed for the especial use of mechanical geniuses, daredevils > > > and lunatics." — George Fitch, Atlanta Constitution Newspaper, > > > 1916 > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
