Bryan Hackney wrote:> As for RS232, it has disappeared from most computers - but USB to async > adapters are around. This might be a good time to ask which ones work > and which ones don't. Believe it or not, there are many USB to async > adapters that just don't work!see: http://www.dontronics.com/usb_232.html for one such device. and have a look at the user feed back at: http://www.dontronics.com/usb_232.html#reviews and for USB to 422/485 using the same chipset: http://www.dontronics.com/usb_485.html Don... -- Don McKenzie E-Mail Contact Page: http://www.e-dotcom.com/ecp.php?un=Dontronics RS-232 to VGA. Many resolutions http://www.dontronics.com/micro-vga.html USB to RS232 Converter that works http://www.dontronics.com/usb_232.html
RS232/485 impromptu survey.
Started by ●September 19, 2005
Reply by ●September 20, 20052005-09-20
Reply by ●September 20, 20052005-09-20
Not Really Me wrote:>>Thanks to TexasInstruments, I found an RS485 driver that does 25MBit over >>160m, and another set that does 3MBit over 500m. So even with a medium >>datarate, my devices can have a serial connection. >> >>Yes, a serial to USB is proposed external to the device. > > Thanks for the comments, please identify the TI driver.These transceivers are the SN65HVD23D & SN65HVD24D, replacement compatible with the industry standard DS75176, and cost 4$ in single quantities at digikey. Rene -- Ing.Buero R.Tschaggelar - http://www.ibrtses.com & commercial newsgroups - http://www.talkto.net
Reply by ●September 20, 20052005-09-20
Not Really Me wrote:> How popular is that old standby async/sync serial data in new embedded > designs? > I know there are lots of other technologies coming into play from ethernet > to wireless, USB, etc., but what percentage of your new designs are using > RS232 or RS485? >All of our designs in the last two years include RS232 and/or R2485, mostly (but not only) async. Some of them have Ethernet ports too, no USB though. Our products have to deal with a lot of serial protocols (some of them almost older than myself) and the problem we are having these days is the lack of good, hardware-assisted serial protocol analyzers. Yes, we have software analyzers, but they need PC's with 2 serial ports (almost extinct) and they always have problems with the software drivers and Windows versions... The other day, our 1989's Thosiba PC with MS-DOS 4.01 and ISA-based LM1 anayzer died, and we are still in mourning for it.
Reply by ●September 20, 20052005-09-20
On Tue, 20 Sep 2005 12:57:45 +0200, Rene Tschaggelar <none@none.net> wrote:>Not Really Me wrote: > >>>Thanks to TexasInstruments, I found an RS485 driver that does 25MBit over >>>160m, and another set that does 3MBit over 500m. So even with a medium >>>datarate, my devices can have a serial connection. >>> >>>Yes, a serial to USB is proposed external to the device. >> >> Thanks for the comments, please identify the TI driver. > >These transceivers are the SN65HVD23D & SN65HVD24D, >replacement compatible with the industry standard >DS75176, and cost 4$ in single quantities at digikey. >NVE has got some isolation 485 drivers that can do 35Mbit. Not sure over what cable length. (Device is the IL485). Just add a small DC-DC Converter and one has a fully galvanically isolated RS485 interface. Regards Anton Erasmus
Reply by ●September 20, 20052005-09-20
Anton Erasmus wrote:> On Tue, 20 Sep 2005 12:57:45 +0200, Rene Tschaggelar <none@none.net> > wrote: > > >>Not Really Me wrote: >> >> >>>>Thanks to TexasInstruments, I found an RS485 driver that does 25MBit over >>>>160m, and another set that does 3MBit over 500m. So even with a medium >>>>datarate, my devices can have a serial connection. >>>> >>>>Yes, a serial to USB is proposed external to the device. >>> >>>Thanks for the comments, please identify the TI driver. >> >>These transceivers are the SN65HVD23D & SN65HVD24D, >>replacement compatible with the industry standard >>DS75176, and cost 4$ in single quantities at digikey. >> > NVE has got some isolation 485 drivers that can do 35Mbit. Not sure > over what cable length. (Device is the IL485). Just add a small > DC-DC Converter and one has a fully galvanically isolated RS485 > interface.Thanks for the link. The point is the distance. Apparently the transmission line requires some tweaking what the above mentioned transceivers do. If ground signals are to be expected, I'd insert a magnetic coupler too. Have a look at the TI application notes on the subject. Rene -- Ing.Buero R.Tschaggelar - http://www.ibrtses.com & commercial newsgroups - http://www.talkto.net
Reply by ●September 22, 20052005-09-22
> How popular is that old standby async/sync serial data in new embedded > designs? > I know there are lots of other technologies coming into play from ethernet > to wireless, USB, etc., but what percentage of your new designs are using > RS232 or RS485? > > I still see it on almost every project. If not as an intended interface > then at least for debugging. > > Your comments are appreciated.We use it for all comms to electronics from other close electronics. Then to PCs or long distances we use ethernet.
Reply by ●September 23, 20052005-09-23
On 19-Sep-2005, "Not Really Me" <scott@exoXYZtech.com> wrote:> I know there are lots of other technologies coming into play from ethernet > > to wireless, USB, etc., but what percentage of your new designs are using > RS232 or RS485?100% of my new designs have RS232, RS485, or both. USB makes sense if you are connecting to a PC, ethernet makes sense if you are connecting to a ethernet network. I'm most concerned with connecting to a radio or wireless modem, located in the same box as my product, mounted on a utility pole (with a 15 inch cable). I'm starting to see a whole new generation of spec writters though, that are only familiar with PCs. They don't seem to understand why ethernet is not the best way to connect two battery powered devices, that are a foot apart. -Hershel
Reply by ●September 23, 20052005-09-23
Ignacio G.T. wrote:> Our products have to deal with a lot of serial protocols (some of them > almost older than myself) and the problem we are having these days is > the lack of good, hardware-assisted serial protocol analyzers. Yes, we > have software analyzers, but they need PC's with 2 serial ports (almost > extinct) and they always have problems with the software drivers and > Windows versions... The other day, our 1989's Thosiba PC with MS-DOS > 4.01 and ISA-based LM1 anayzer died, and we are still in mourning for it.Guess why I keep my Bondwell 286 laptop. Hint: look in back. Thad
Reply by ●September 25, 20052005-09-25
On Thu, 22 Sep 2005 17:36:52 +1000, "DarkD" <darkd@NOSPAMoptusworld.com.SPAM.au> wrote:>> How popular is that old standby async/sync serial data in new embedded >> designs? >> I know there are lots of other technologies coming into play from ethernet >> to wireless, USB, etc., but what percentage of your new designs are using >> RS232 or RS485? >> >> I still see it on almost every project. If not as an intended interface >> then at least for debugging. >> >> Your comments are appreciated. > >We use it for all comms to electronics from other close electronics. Then to >PCs or long distances we use ethernet. >My reason for RS-232 is realy simple, less code overhead. Why do something with 100+ lines of code when you can do it with 10? Not to mention, at least in my case, it is cheap. Most of my apps only need to send less then 1024 bytes.
Reply by ●September 25, 20052005-09-25
On Fri, 23 Sep 2005 21:24:18 -0600, Thad Smith <ThadSmith@acm.org> wrote:>Ignacio G.T. wrote: > >> Our products have to deal with a lot of serial protocols (some of them >> almost older than myself) and the problem we are having these days is >> the lack of good, hardware-assisted serial protocol analyzers. Yes, we >> have software analyzers, but they need PC's with 2 serial ports (almost >> extinct) and they always have problems with the software drivers and >> Windows versions... The other day, our 1989's Thosiba PC with MS-DOS >> 4.01 and ISA-based LM1 anayzer died, and we are still in mourning for it. > >Guess why I keep my Bondwell 286 laptop. Hint: look in back. > >ThadIf you look around you can still find MBs with serial ports, well at least one, gigabyte does a few. Also PCI serial cards, all though rare can still be found, I picked up a few for NZ$1 a peice. Not to mention I have a few ISA ones stock piled. The big pain is OEM software that will not work on anything faster then a 386!!! but using programs like atslow I can get most of them working, even on a 1.8GHz P4, running MSDOS that is ;)
