Re: [SOLVED!] Communicating with USB Modem
I was going to just reply to Phil privately, but there are a few points that could effect someone else's decision in a similar case, so I'm going to address them on list. Phil makes some good points, so I thought it appropriate to include my thoughts on them. On Oct 18, 2010, at 12:38 AM, Phil Requirements wrote: On 2010-10-13 22:28:10 -0400, Hal Vaughan wrote: Comments and some info at the bottom, so it makes sense when you read it. (Hey, there's NO way I'm going to top post on this list!) Now I have a few notes on this, since there's been a few private conversations with people who are in or have seen this thread. 1) I'm basically making a black box for the people I'm working with. I do NOT want them messing with the computer I give them. Many times, in embedded systems, there is no PCI slot. Sometimes there is, but I can't count on that. (I haven't picked my hardware config yet.) So I really need an external modem since the only connection I can count on is a USB connector. (Even with embedded, most systems have 2 or more USB connectors, and some people may need to hook up a printer there.) I see that here in Point 1 you rule out a PCI card-based solution while also admitting that the hardware has not yet been specified. It seems feasible that if you found a really great and cheap PCI modem, you could spec the hardware around that. I spent close to a week researching possible mobos or all-in-one package systems. Some boards do have PCI slots, but some don't, so that's a big issue to consider. I'd much rather be able to spec the hardware around the mobo than a modem. Also, if I go for something like Soekris, which I like, but which may cost more than I want (they still haven't released final specs and cost on their Net6501, which is what I'd likely use), using a PCI card would be problematical. While I've seen PCI slots on their boards, I'd have to cut a hole in it to allow someone to plug a phone cable in. That's one of the two biggest strikes against a PCI modem: I can't be sure how it'll fit in with the rest, and finding an appropriate mobo or mobo/case combo is a bigger concern than using a PCI modem. If I go in order of my reasoning, I listed that as strike 2 against PCI modems. I mention this because it seems to me that an external USB modem is not very black box. There would be your discrete little appliance with a very conspicuous dongle coming off it. A PCI internal modem that fits inside the appliance would be much more black-box-like. I agree. Until I read how you phrased it here, I had not thought of stating my reasoning here. I'll be working intelligent people who work in technical fields, but not in computer fields. The tradeoff is that if I need someone in another city to work with me so I can walk them through solving a problem so I don't have to make 4-10 hour round trip to get there and end up just flipping a switch, that's good, since they can work with me. But, on the flip side, when you're working with someone with an intelligent and technical mind, they're the ones more likely to think they can break the rules in some way because they know they're smart. I'm more concerned about this being black boxy in terms of them not trying to log on or hook up a keyboard and monitor than anything else. I don't want them thinking of this box as a computer where, if it starts acting odd, they think they can work with. On the other hand, even though I'm within 8 miles of the state capital building, I didn't get broadband for years, due to bureaucratic attitudes at the cable company (which kept changing ownership) and Verizon. I had to work with Linux and dial-up modems for several years. I also had to replace my PCI modems every few months. I don't remember why, but I do remember tossing out a lot of PCI modems that worked and stopped working. Sometimes it was due to a distro upgrade, other times it was a new modem that docs said would work that didn't. If a PCI modem goes bad on me, then it means paying for them to ship me the unit overnight, me replacing it and sending it back overnight. If a USB modem goes bad, it means having a new one drop-shipped from Newegg. Considering package size, that's much easier and cheaper than replacing a PCI modem. That, on my list, was strike 3 against PCI. The problem with PCI card modems is that they are not so likely to support GNU/Linux. So they aren't a clear winner. But they would be better for a black box. And that was my strike 1 against PCI -- along with seeing some work now and not with later drivers. As I said, my black box was a bit of a compromise. It's a black box as far as being something a user can log onto, but not 100% in that it has the external modem. Still, what I'm looking at now includes the embedded box, a PCI modem, and a wall-wart transformer. All the user has to do on receiving it is plug in a CAT5, plug in the USB modem, plug
Re: [SOLVED!] Communicating with USB Modem
On 2010-10-13 22:28:10 -0400, Hal Vaughan wrote: Comments and some info at the bottom, so it makes sense when you read it. (Hey, there's NO way I'm going to top post on this list!) Now I have a few notes on this, since there's been a few private conversations with people who are in or have seen this thread. 1) I'm basically making a black box for the people I'm working with. I do NOT want them messing with the computer I give them. Many times, in embedded systems, there is no PCI slot. Sometimes there is, but I can't count on that. (I haven't picked my hardware config yet.) So I really need an external modem since the only connection I can count on is a USB connector. (Even with embedded, most systems have 2 or more USB connectors, and some people may need to hook up a printer there.) I see that here in Point 1 you rule out a PCI card-based solution while also admitting that the hardware has not yet been specified. It seems feasible that if you found a really great and cheap PCI modem, you could spec the hardware around that. I mention this because it seems to me that an external USB modem is not very black box. There would be your discrete little appliance with a very conspicuous dongle coming off it. A PCI internal modem that fits inside the appliance would be much more black-box-like. The problem with PCI card modems is that they are not so likely to support GNU/Linux. So they aren't a clear winner. But they would be better for a black box. 2) I can't count on having an RS232 interface, so that rules out a lot of good modems. Another problem with these hardware modems is that they are large and require their own power supply, so they are not at all resembling a black box. 3) Yes, I know about US Robotics, I have known about them since my Apple ][e days. (Yes, I'm that ancient!) However, their modem is almost twice as much as this one and if things go well, I could need 20 or more of these systems, and 20 * $20 = $400. That pays for 40 group Argentine tango lessons or almost pays for a 10 pack of private ballroom lessons. I'd rather be dancing with women than spending extra on modems when I don't have to. I know that's just crazy and silly, but that's the way I am. Don't pay more than you have to, as long as everything works to your standard. 4) I spent the better part of an afternoon and evening on trying to get the Encore modem to work and couldn't, so I ordered the Rosewill one. Yes, I'd love to have pursued it, but considering that, at this point, I'm only working with one modem and not mass-ordering them, it makes no sense to spend hours on making a modem work when $30 will get me one that should work. Again, I know it's silly, but I'd rather be dancing with women than working at my computer. At some point, if an idea hits me, I may go back to working on the Encore modem, but for now I don't see the point of investing more time in it. I agree that for your purposes it does not make sense to try to make the Encore modem work, since you are trying to set up something worth replicating. Why spend many hours battling a modem if you don't have to? Thanks to all that helped me with this. I would love it if I didn't need to add another package, especially one not in repositories, but this works and it doesn't take much to work, and including this package as part of my setup won't be too hard at all. I don't know what kind of reputation Rosewill has, but I've had good luck with them, so I'll be sticking with their modem for now and when I get to doing the mass-ordering as well. If people still have more suggestions, I'm still open, but I'm not going to spend hours Googling or researching or compiling to get the Encore working. Again, thanks for the help! Hal Thank you for posting the update on this issue. It is interesting to know the outcome of all the work you are doing. I think you Rosewill solution is fine, though I would want to make sure it performs well over time before deploying two dozen of them. I only responded because I have this nagging feeling that, as long as you're going to all this trouble, a PCI card-based solution would be a lot more black-box-like. On the other hand, I get the feeling that you do not want the RD phase to go on for a long time, because it is cutting in to your other interests. In which case you might not want to investigate every possible approach. Phil -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20101018043839.ga29...@kasploosh.net
Re: [SOLVED!] Communicating with USB Modem
Comments and some info at the bottom, so it makes sense when you read it. (Hey, there's NO way I'm going to top post on this list!) On Oct 9, 2010, at 3:21 AM, Hal Vaughan wrote: I have a Debian Lenny system and I've plugged in a USB 56K modem. (I know that's as outdated as a Model T, but I need it for business.) When I type cat /proc/bus/usb/devices I get this: T: Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=480 MxCh= 8 B: Alloc= 0/800 us ( 0%), #Int= 0, #Iso= 0 D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=1d6b ProdID=0002 Rev= 2.06 S: Manufacturer=Linux 2.6.26-2-686 ehci_hcd S: Product=EHCI Host Controller S: SerialNumber=:00:1d.7 C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr= 0mA I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub E: Ad=81(I) Atr=03(Int.) MxPS= 4 Ivl=256ms T: Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2 B: Alloc= 0/900 us ( 0%), #Int= 0, #Iso= 0 D: Ver= 1.10 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=1d6b ProdID=0001 Rev= 2.06 S: Manufacturer=Linux 2.6.26-2-686 uhci_hcd S: Product=UHCI Host Controller S: SerialNumber=:00:1d.0 C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr= 0mA I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub E: Ad=81(I) Atr=03(Int.) MxPS= 2 Ivl=255ms T: Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 0 D: Ver= 2.00 Cls=ff(vend.) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=047e ProdID=2892 Rev= 2.00 S: Manufacturer=Agere Systems S: Product=Agere USB2.0 V.92 SoftModem C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=200mA I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none) E: Ad=82(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms E: Ad=02(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms I: If#= 0 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none) E: Ad=82(I) Atr=01(Isoc) MxPS= 32 Ivl=1ms E: Ad=02(O) Atr=01(Isoc) MxPS= 32 Ivl=1ms I: If#= 0 Alt= 2 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none) E: Ad=81(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=01(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=82(I) Atr=03(Int.) MxPS= 16 Ivl=16ms From what I can find, that means the actual device file for this modem should be at /dev/bus/usb/001/002, but I know I could be wrong on that. I'm trying to communicate with this modem. I've used Minicom, with the device I mentioned above. There are no /dev/ttyACM0 devices, as sometimes happens with a modem. I've tried all /dev/ttySx, where x is from 0 to 4, with no results. The problem with Minicom is that it can take time and a lot of frustrating keypresses to try one device after another. Also, I'm not sure the serial port speed settings are at all appropriate in Minicom for USB modems. I was also trying a Perl program that would simply fork, have the parent open the device for reading and listen, then the child would open the same device for writing and send ATZ through to the device, then I could watch for a response -- but then when I tried it on a system with a serial port where I knew the device was /dev/ttyS0, it didn't work, so maybe there's a problem with the program. (I don't want to post a full Perl program here, since this isn't a Perl board that focuses on debugging Perl.) This is a test situation, so I can't be sure the modem works with Linux, but I would think if it's external and USB, it would have to accept serial commands sent over the USB port. I could be wrong on this, of course. So here's the questions: 1) What device should I be able to write to and read from to connect to this modem? 2) Any suggestions on how to write to and read from the device? (Write to it in Perl or use echo in bash -- but then how do I read to see results?) 3) Any other ideas or suggestions on how to control and use this modem in Linux (without going into C or C++)? Even after playing around for a while, and with help from others (see other emails in this thread), I could not get the other modem to work properly. I did try the sl-modem drivers from the non-free repositories. They would create /dev/modem and link it to /dev/ttySL0, but even with that, it wouldn't work. When I tested any modem, I did two things: 1) I used Minicom, which is a great term program, and 2) I used my own Perl program that would open a device as a file to read and write to, then send the ATZ command (with a newline character after it) and I'd see if anything came back. I missed a few details on this program, but once I got it to work (tested it on an RS232 modem on another box), I would see the ATZ printed on the console (as well as knowing it was supposedly sent to the device) and I'd see a blank line, then OK. No matter what I did with Minicom or my Perl script, I could not communicate with the Encore modem. Today I received another USB modem, a Rosewill RNX-56USB from NewEgg. The link to that item is:
