I’ve got a USB webcam, and a 9pin basic stamp and a 9pin servo controller. I want to make a computer controlled R/C bot without having to take on a mortgage to buy the parts.
The Wiport rocks, but doesnt support the controlling of a USB device. I’ve seen wireless USB servers that are great, but dont support 9pin serial devices like the SSC-32. Is there something out there that can in fact support both a powered USB device (like a webcam) as well as a 9pin port for the SSC or basic stamp?
Alternately, is there such a thing as a 9pin serial webcam?
Why not use a USB-to-serial converter to with the wireless USB server? If you don’t mind getting your hands dirty, use a 2 port server with 1 for the camera and then buy a DLP-2232M module from Mouser ($35) to get two (2) TTL serial ports from the other USB port. If you “need” RS-232 to talk to the other devices you’ll need to add a MAX232 and 5 small tant. caps but this is all easy stuff to wire up on a small plug/proto board.
If your a hand off kind of persion buy a 4-port USB server and 2 USB-to-RS232 adapters to get the same answer (for more money) and an extra USB port to do whatever.
Eddie’s right, assuming you can use a USB hub with the wireless server or have enough ports, many types of USB to RS-232 adapters exist. FTDI makes some nice modules too, sparkfun.com/commerce/product_info.php?products_id=718, giving one TTL serial port for $15. If space/ drivers aren’t a concern, you might be able to get away with using regular USB to serial adapters for PCs, which you can get cheaper.
Remember that not all wireless USB servers are created equal. You would want to be certain that whatever device you selected would work with more than just HID and printer devices. A camera or memory device might require a higher speed type of USB endpoint that the wireless nature of a wireless connection might not deal with well. Choosy mothers read the bludy label.
I was considering trying to splice together a hub and a USB to 9pin adapter, but I am worried about power issues as well as bandwidth. I have never seen a USB hub designed to power itself off batteries and I do not know enough about the USB specs to go splicing in, say a tap off the bots power supply into the hub. Ah well, guess I’ll just have to get off me ■■■■ and study, but I was just looking to not have to reinvent the wheel if anyone knew of a wireless module that did both.
The wireless USB device, assuming it can power a single high power USB (500 mA) should be able to power a four port hub and four low power devices all on its own, so you may not need an extra power system. The battery life of the hub (assuming it is battery powered) may not be optimal at this configuration though.
Even if this wasn’t the case, just a self-powered hub could take care of your power needs assuming the transmitter could support it. It has all the electronics to take care of the USB spec., so you don’t have to. You just connect it to a regulated 5V source off of the bot’s main power supply instead of using the power adaptor. The max capacity of the wall transformers of most 4-port self powered hubs are 2A (covering 4 high power devices), but since the devices you want to power are all probably USB low power devices (100 mA max), you probably wouldn’t need anywhere near as much. I’m thinking a good bet would be in the 500-750 mA range.
Again, if you can, please post links to the wireless USB system you are planning to use since much of the system depends on the details of the transmitter. I know Belkin had a $75 one that basically is just a wireless bridge and a self powered USB hub, and appears transparent to the host PC as if the devices were attached with a cable. This is nice since its cross-platform. The range on that was lousy (10-30 ft) if I recall correctly, the idea being you attach the dongle to a laptop and then use it instead of a dock, one of the reasons I never bought one. However, newer or different models might actually provide useable range.
Finally, I might point out that you could always use a Bluetooth RS-232 device in addition if your wireless USB couldn’t use a hub or other problems came up. At sparkfun they have a number of devices for around $50. Check out the “bluetooth primer” tutorial, they managed to set up a remote serial LCD in minutes. I was quite impressed and was going to get one of those before I knew about the WiPort. My bluetooth devices generally get around 100 ft worth of range, and probably would do better if I hacked some higher dB antennas onto them. However, since my University has campus wide handoff capable (i.e. same IP) WiFi, the WiPort has major range benefits for my situation if I needed a wireless serial interface.
I’d be interested in this communication possibility if anyone finds something that would work. Silex at least supports USB serial devices. Anyone found a simple USB print server that supports a serial USB cable?.
to do it cheaply i would just get a wireless camera (mine is a 200mw) a tuner card for you’r pc
and a pc to r/c cable here,s 1 endurance-rc.com/pctx.html if u got a trainerport on your tranmitter that is.
image analizing is beyond my skill level (i,m a noob) atleast for awhile
so i havent even looked at the CMU type camera stuff yet…
