* usb serial programming @ 2014-07-21 3:19 Amadeus W.M. 2014-07-21 18:18 ` Greg KH 2014-07-22 5:12 ` Sudip Mukherjee 0 siblings, 2 replies; 12+ messages in thread From: Amadeus W.M. @ 2014-07-21 3:19 UTC (permalink / raw) To: kernelnewbies Not sure if this is the right venue for this question, please direct me to the right place if it's not. I have a C program that opens the serial port /dev/ttyS0 and sends commands (as strings) back and forth to a pan-tilt-zoom camera. That works very well, but I want to use the camera with a Raspberry Pi, which of course does not have a serial port (RS232). One option is to use a RS232 to usb adapter and rewrite the C code for the usb port. So how do I go about that? Is usb serial port programming possible and documented anywhere? Thanks! ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 3:19 usb serial programming Amadeus W.M. @ 2014-07-21 18:18 ` Greg KH 2014-07-21 18:27 ` Bruce Rowen 2014-07-21 18:55 ` Amadeus W.M. 2014-07-22 5:12 ` Sudip Mukherjee 1 sibling, 2 replies; 12+ messages in thread From: Greg KH @ 2014-07-21 18:18 UTC (permalink / raw) To: kernelnewbies On Mon, Jul 21, 2014 at 03:19:00AM +0000, Amadeus W.M. wrote: > Not sure if this is the right venue for this question, please direct me to > the right place if it's not. > > I have a C program that opens the serial port /dev/ttyS0 and sends commands > (as strings) back and forth to a pan-tilt-zoom camera. That works very well, > but I want to use the camera with a Raspberry Pi, which of course does not > have a serial port (RS232). One option is to use a RS232 to usb adapter and > rewrite the C code for the usb port. So how do I go about that? Is > usb serial port programming possible and documented anywhere? Nothing to "rewrite", just point your code at /dev/ttyUSB0 instead, and away you go... ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 18:18 ` Greg KH @ 2014-07-21 18:27 ` Bruce Rowen 2014-07-21 19:05 ` Amadeus W.M. 2014-07-21 18:55 ` Amadeus W.M. 1 sibling, 1 reply; 12+ messages in thread From: Bruce Rowen @ 2014-07-21 18:27 UTC (permalink / raw) To: kernelnewbies Assuming your camera is RS232, you can use a simple RS232 daughter card on the Raspberry (about $7 from MCM electronics and others). I have done this exact thing for communications with an old RS232 device. Alternative is of course a USB to RS232 adapter and as Greg writes, you just change the target device file (the $7 adapter also creates a /dev/ttyxxx device. -Bruce On Jul 21, 2014, at 12:18 PM, Greg KH <greg@kroah.com> wrote: > On Mon, Jul 21, 2014 at 03:19:00AM +0000, Amadeus W.M. wrote: >> Not sure if this is the right venue for this question, please direct me to >> the right place if it's not. >> >> I have a C program that opens the serial port /dev/ttyS0 and sends commands >> (as strings) back and forth to a pan-tilt-zoom camera. That works very well, >> but I want to use the camera with a Raspberry Pi, which of course does not >> have a serial port (RS232). One option is to use a RS232 to usb adapter and >> rewrite the C code for the usb port. So how do I go about that? Is >> usb serial port programming possible and documented anywhere? > > Nothing to "rewrite", just point your code at /dev/ttyUSB0 instead, and > away you go... > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 18:27 ` Bruce Rowen @ 2014-07-21 19:05 ` Amadeus W.M. 2014-07-21 19:42 ` Bruce Rowen 0 siblings, 1 reply; 12+ messages in thread From: Amadeus W.M. @ 2014-07-21 19:05 UTC (permalink / raw) To: kernelnewbies On Mon, 21 Jul 2014 12:27:44 -0600, Bruce Rowen wrote: > Assuming your camera is RS232, you can use a simple RS232 daughter card on the Raspberry (about $7 from MCM electronics and others). > I have done this exact thing for communications with an old RS232 device. > > Alternative is of course a USB to RS232 adapter and as Greg writes, you just change the target device file (the $7 adapter also creates a /dev/ttyxxx device. > > -Bruce > On Jul 21, 2014, at 12:18 PM, Greg KH <greg@kroah.com> wrote: > Thank you, that's useful. This, you mean? http://www.mcmelectronics.com/product/83-15630 This one is for Arduino. I couldn't find one for Pi on the MSM site, but knowing what to search for lead me to a plethora of expansion cards for the RPi: http://elinux.org/RPi_Expansion_Boards#RS232_to_TTL_converter Thank you for the pointer. ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 19:05 ` Amadeus W.M. @ 2014-07-21 19:42 ` Bruce Rowen 0 siblings, 0 replies; 12+ messages in thread From: Bruce Rowen @ 2014-07-21 19:42 UTC (permalink / raw) To: kernelnewbies On Jul 21, 2014, at 1:05 PM, "Amadeus W.M." <amadeus84@verizon.net> wrote: > On Mon, 21 Jul 2014 12:27:44 -0600, Bruce Rowen wrote: > >> Assuming your camera is RS232, you can use a simple RS232 daughter card on the Raspberry (about $7 from MCM electronics and others). >> I have done this exact thing for communications with an old RS232 device. >> >> Alternative is of course a USB to RS232 adapter and as Greg writes, you just change the target device file (the $7 adapter also creates a /dev/ttyxxx device. >> >> -Bruce >> On Jul 21, 2014, at 12:18 PM, Greg KH <greg@kroah.com> wrote: >> > > Thank you, that's useful. This, you mean? > > http://www.mcmelectronics.com/product/83-15630 It looks like they may no longer carry it, sorry. There are others out there, try googling 'raspberry serial port GPIO adapter' > > This one is for Arduino. I couldn't find one for Pi on the MSM site, but > knowing what to search for lead me to a plethora of expansion cards for > the RPi: > > http://elinux.org/RPi_Expansion_Boards#RS232_to_TTL_converter The USB-serial adapter may be the more expedient solution at this point, Good luck! > > Thank you for the pointer. > > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 18:18 ` Greg KH 2014-07-21 18:27 ` Bruce Rowen @ 2014-07-21 18:55 ` Amadeus W.M. 2014-07-21 19:06 ` Greg KH 1 sibling, 1 reply; 12+ messages in thread From: Amadeus W.M. @ 2014-07-21 18:55 UTC (permalink / raw) To: kernelnewbies On Mon, 21 Jul 2014 11:18:28 -0700, Greg KH wrote: > On Mon, Jul 21, 2014 at 03:19:00AM +0000, Amadeus W.M. wrote: >> Not sure if this is the right venue for this question, please direct me to >> the right place if it's not. >> >> I have a C program that opens the serial port /dev/ttyS0 and sends commands >> (as strings) back and forth to a pan-tilt-zoom camera. That works very well, >> but I want to use the camera with a Raspberry Pi, which of course does not >> have a serial port (RS232). One option is to use a RS232 to usb adapter and >> rewrite the C code for the usb port. So how do I go about that? Is >> usb serial port programming possible and documented anywhere? > > Nothing to "rewrite", just point your code at /dev/ttyUSB0 instead, and > away you go... Thanks for the prompt answer! That's what I was hoping for, and I would have tried that, but I don't have any /dev/ttyUSBX. I am connecting the camera to a usb to RS232 cable: http://www.amazon.com/gp/product/B000BI95W0/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 Does this mean my adapter is not supported by linux? Also, nothing happens in /var/log/messages when I plug the cable into the usb port. This is my lsusb: 1) root:~> lsusb Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 005 Device 003: ID 0c45:1050 Microdia CF Card Reader Bus 005 Device 002: ID 046d:c016 Logitech, Inc. Optical Wheel Mouse Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 008: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 005: ID 04fc:0561 Sunplus Technology Co., Ltd Flexcam 100 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub No trace of the adapter. Should /dev/ttyUSB0 pop up when I plug the adapter into the usb port, even before I connect anything to the serial port of the cable? If the adapter is not supported, can I write a driver for it? I'll be happy to, with a little guidance to get me started. Any pointers? Thanks! ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 18:55 ` Amadeus W.M. @ 2014-07-21 19:06 ` Greg KH 2014-07-21 19:25 ` Amadeus W.M. 0 siblings, 1 reply; 12+ messages in thread From: Greg KH @ 2014-07-21 19:06 UTC (permalink / raw) To: kernelnewbies On Mon, Jul 21, 2014 at 06:55:43PM +0000, Amadeus W.M. wrote: > On Mon, 21 Jul 2014 11:18:28 -0700, Greg KH wrote: > > > On Mon, Jul 21, 2014 at 03:19:00AM +0000, Amadeus W.M. wrote: > >> Not sure if this is the right venue for this question, please direct me to > >> the right place if it's not. > >> > >> I have a C program that opens the serial port /dev/ttyS0 and sends commands > >> (as strings) back and forth to a pan-tilt-zoom camera. That works very well, > >> but I want to use the camera with a Raspberry Pi, which of course does not > >> have a serial port (RS232). One option is to use a RS232 to usb adapter and > >> rewrite the C code for the usb port. So how do I go about that? Is > >> usb serial port programming possible and documented anywhere? > > > > Nothing to "rewrite", just point your code at /dev/ttyUSB0 instead, and > > away you go... > > Thanks for the prompt answer! > > That's what I was hoping for, and I would have tried that, but I don't > have any /dev/ttyUSBX. I am connecting the camera to a usb to RS232 > cable: > > http://www.amazon.com/gp/product/B000BI95W0/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 > > Does this mean my adapter is not supported by linux? Also, nothing > happens in /var/log/messages when I plug the cable into the usb port. > This is my lsusb: > > 1) root:~> lsusb > Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub > Bus 005 Device 003: ID 0c45:1050 Microdia CF Card Reader > Bus 005 Device 002: ID 046d:c016 Logitech, Inc. Optical Wheel Mouse > Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 004 Device 008: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS > Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 003 Device 005: ID 04fc:0561 Sunplus Technology Co., Ltd Flexcam 100 > Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub > > No trace of the adapter. What is the: Bus 004 Device 008: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS device? > Should /dev/ttyUSB0 pop up when I plug the adapter into the usb port, > even before I connect anything to the serial port of the cable? Yes. What happens in the kernel log when you plug the device into the system? Try doing: dmesg -c # plug in the adapter now dmesg to just see the log messages for that, and not the whole kernel boot log. > If the adapter is not supported, can I write a driver for it? I'll be happy to, > with a little guidance to get me started. Any pointers? Odds are the device id just needs to be added to an existing driver as I do not know of any "new" usb-serial converter chips that Linux does not already support. thanks, greg k-h ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 19:06 ` Greg KH @ 2014-07-21 19:25 ` Amadeus W.M. 2014-07-21 19:46 ` Greg KH 0 siblings, 1 reply; 12+ messages in thread From: Amadeus W.M. @ 2014-07-21 19:25 UTC (permalink / raw) To: kernelnewbies > > What is the: > Bus 004 Device 008: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS > > device? That's my backup power supply. > >> Should /dev/ttyUSB0 pop up when I plug the adapter into the usb port, >> even before I connect anything to the serial port of the cable? > > Yes. > > What happens in the kernel log when you plug the device into the system? > > Try doing: > dmesg -c > # plug in the adapter now > dmesg > to just see the log messages for that, and not the whole kernel boot > log. > 2) root:~> dmesg -c #plug-in adapter 3) root:~> dmesg Absolutely nothing. I also did tail -f /var/log/messages then plugged in the adapter, and again, everything seems dead. The USB port is ok, because other devices (e.g. the Fushicai video grabber) do work. >> If the adapter is not supported, can I write a driver for it? I'll be happy to, >> with a little guidance to get me started. Any pointers? > > Odds are the device id just needs to be added to an existing driver as > I do not know of any "new" usb-serial converter chips that Linux does > not already support. > Oh, one more thing. Reading about these converters, I saw many use an ftdi chip, so I did modprobed ftdi_elan and ftdi_sio: 7) root:~> lsmod | grep ftdi ftdi_elan 36689 0 ftdi_sio 48770 0 In fact, the dmesg above was with the ftdi modules loaded. ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 19:25 ` Amadeus W.M. @ 2014-07-21 19:46 ` Greg KH 2014-07-23 0:26 ` Amadeus W.M. 0 siblings, 1 reply; 12+ messages in thread From: Greg KH @ 2014-07-21 19:46 UTC (permalink / raw) To: kernelnewbies On Mon, Jul 21, 2014 at 07:25:24PM +0000, Amadeus W.M. wrote: > > > > What is the: > > Bus 004 Device 008: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS > > > > device? > > That's my backup power supply. > > > > > >> Should /dev/ttyUSB0 pop up when I plug the adapter into the usb port, > >> even before I connect anything to the serial port of the cable? > > > > Yes. > > > > What happens in the kernel log when you plug the device into the system? > > > > Try doing: > > dmesg -c > > # plug in the adapter now > > dmesg > > to just see the log messages for that, and not the whole kernel boot > > log. > > > 2) root:~> dmesg -c #plug-in adapter > 3) root:~> dmesg > > Absolutely nothing. I also did > > tail -f /var/log/messages Then USB isn't working :( Or the device isn't, can you plug it into some other computer to test it out? > then plugged in the adapter, and again, everything seems dead. The USB port > is ok, because other devices (e.g. the Fushicai video grabber) do work. Sounds like a broken device. > >> If the adapter is not supported, can I write a driver for it? I'll be happy to, > >> with a little guidance to get me started. Any pointers? > > > > Odds are the device id just needs to be added to an existing driver as > > I do not know of any "new" usb-serial converter chips that Linux does > > not already support. > > > > Oh, one more thing. Reading about these converters, I saw many use an > ftdi chip, so I did modprobed ftdi_elan and ftdi_sio: > > 7) root:~> lsmod | grep ftdi > ftdi_elan 36689 0 > ftdi_sio 48770 0 > > In fact, the dmesg above was with the ftdi modules loaded. You should get some kernel log messages when a new USB device is plugged in, no matter what type it is. The fact that you are not is a problem. greg k-h ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 19:46 ` Greg KH @ 2014-07-23 0:26 ` Amadeus W.M. 0 siblings, 0 replies; 12+ messages in thread From: Amadeus W.M. @ 2014-07-23 0:26 UTC (permalink / raw) To: kernelnewbies >> In fact, the dmesg above was with the ftdi modules loaded. > > You should get some kernel log messages when a new USB device is plugged > in, no matter what type it is. The fact that you are not is a problem. > > greg k-h Do you suppose this would work? http://www.amazon.com/gp/product/B006PIU2KO/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3CTCSJRE9G6AY ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-21 3:19 usb serial programming Amadeus W.M. 2014-07-21 18:18 ` Greg KH @ 2014-07-22 5:12 ` Sudip Mukherjee 2014-07-23 0:29 ` Amadeus W.M. 1 sibling, 1 reply; 12+ messages in thread From: Sudip Mukherjee @ 2014-07-22 5:12 UTC (permalink / raw) To: kernelnewbies On Mon, Jul 21, 2014 at 8:49 AM, Amadeus W.M. <amadeus84@verizon.net> wrote: > Not sure if this is the right venue for this question, please direct me to > the right place if it's not. > > I have a C program that opens the serial port /dev/ttyS0 and sends commands > (as strings) back and forth to a pan-tilt-zoom camera. That works very well, > but I want to use the camera with a Raspberry Pi, which of course does not > have a serial port (RS232). One option is to use a RS232 to usb adapter and > rewrite the C code for the usb port. So how do I go about that? Is > usb serial port programming possible and documented anywhere? Raspberry PI is not having a dedicated serial port but GPIO14 and GPIO15 are the Rx and Tx pins , so you can just connect a max3232 to have a serial port . ^ permalink raw reply [flat|nested] 12+ messages in thread
* usb serial programming 2014-07-22 5:12 ` Sudip Mukherjee @ 2014-07-23 0:29 ` Amadeus W.M. 0 siblings, 0 replies; 12+ messages in thread From: Amadeus W.M. @ 2014-07-23 0:29 UTC (permalink / raw) To: kernelnewbies > Raspberry PI is not having a dedicated serial port but GPIO14 and > GPIO15 are the Rx and Tx pins , so you can just connect a max3232 to > have a serial port . I believe that requires some capacitors and possibly some electronics, so I ordered one ready-made from China for $3 including shipping. It's on its way. Slowly. ^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2014-07-23 0:29 UTC | newest] Thread overview: 12+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2014-07-21 3:19 usb serial programming Amadeus W.M. 2014-07-21 18:18 ` Greg KH 2014-07-21 18:27 ` Bruce Rowen 2014-07-21 19:05 ` Amadeus W.M. 2014-07-21 19:42 ` Bruce Rowen 2014-07-21 18:55 ` Amadeus W.M. 2014-07-21 19:06 ` Greg KH 2014-07-21 19:25 ` Amadeus W.M. 2014-07-21 19:46 ` Greg KH 2014-07-23 0:26 ` Amadeus W.M. 2014-07-22 5:12 ` Sudip Mukherjee 2014-07-23 0:29 ` Amadeus W.M.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).