Is there an USB adept out there who would know if this is technically and programmatically possible:
A loopback connection via USB with an external Switch. USB+ and USB- are bridged via an external switch or button. Every 20ms or so, a packet is being sent to the device itself. If the switch is closed, the packet can be received, which fires an event (probably an error because of bouncing), but an event that can nonetheless be handled as an user input.
_________ usb+
| -------------
device | \ button/switch
USB | -------------
--------- usb-
Any idea?
Are there libraries available for eVC++ that expose the USB port as a virtual COM port?
Reason for asking: with external switches and an accessibility software, the devices become accessible for handicapped users. Up until now, legacy RS232 hardware handshake could be used to generate an user input, but these interfaces tend to become extinct with the newer devices.
Thanks for any hint
Phil
Related
I saw some articles about USB Hosting on PDAs, and it took my attention very much, by this gate we can extend our Jam usage in variable ways, attaching USB flashdisks, HDs, digital cameras etc. Anyone has any idea on this issue ?
not possible. you need a usb host. the magician can only act as slave and not as host to a other device. not even with software because that's the way usb works. to keep cost low the chips for usb communication are mostly on a master and not the slave.
further more what could have been done is to connect both devices as slaves to a master and let it act as bridge (there are several devices that work that way) but since the magician doesn't support the mass storage device profile even this isn't possible.
After having a quick chat with cr2 about the process of linux i was surprised to see that external usb host support on the universal is still unknown (obv it uses usb host internally for phone)
basically i have a dongle which on one end has a mini-usb plug (i.e. goes in phone) and on the other end has a usb a receptacle.. i got it with a development kit for an AVR micro-controller that has onboard usb client/host... plugging in the cable switches its mode.
now from what i understand of the pxa270 dev manual
http://www.balloonboard.org/hardware/300/ds/PXA270-dev-manual.pdf
(section 20.4) is that the chip has 3 onboard host ports. the first is dedicated (which i assume is the one used for the phone) the other 2 are shared by usb client mode and must be configured to use host mode. there also is usb-otg supported on chip which may be how things are set up.
to me this suggests that physically the external usb port we have access to can be set to host mode via setting registers (or some software based setup) however i have not looked properly at the pin layout (and electronics is only a hobby) so if someone could try and decipher from this doc
http://pdf1.alldatasheet.net/datasheet-pdf/view/82521/INTEL/PXA270/datasheet.pdf
to progress we need to see whether this is the case or whether there is a physical aspect to setting host mode (if there is then seeing if it wired up)
then we need someone with a bit of low level coding skills (prob linux based coding route) to do any initialisation then on to testing.
as i said i have a dongle but i'm not willing to risk my exec (poor student y'see) until i know a few bits... i have no intention of frying my phone due to test usb device drawing to much power from phone and melting something (i am not sure how the usb spec handles it...i know pc's shut the port down if it draws too much power but a pda i'm not so sure... especially if it isn't expecting it!)
what are other peoples thoughts on all this can anyone investigate anything or verify any of my thoughts etc
i'd like to settle the mystery which ever way it turns out...usb host mode under linux would sure be shiny
it would also be interesting to see whether the 3rd port is connected up
also see section 12 of the first pdf it covers more in depth the details regarding usb
It was suggested in the Titan forum on another subject that this type of discussion would be more appropriate and fruitful in the developer area.
I have just enough knowledge and experience to be dangerous with a soldering iron and electronic parts.
Connecting Keyboard Like Devices via USB or Bluetooth To Mogul
I have searched through the posts here and in other forums and have not found a precise or complete answer to these questions. Any help would be appreciated. I'm not an expert. I did read one post about using the Mogul as a control device ( keyboard ) however a very useful application is to use the Mogul as a data collection device in the field, especially when end users may have devices all ready connecting to laptops/desktops via the USB and seen as ASCII output ( like a 101 keyboard ).
Does the Mogul have USB host capability through the connector? There seems to be conflicting opinions. If it does what is needed to turn on the capability?
This is the scenario I am trying create without having to rebuild or build new devices. A cost effective solution is the goal.
Assume the data collection devices I want to connect to the Mogul have a standard USB connector and wiring the same as a USB 101 type keyboard ( though the devices are not keyboards ) and the signals coming out of the connector are the same. The data stream is ASCII character stream. The USB devices are self powered so they do not need to draw the 5 volts from the Mogul.
The goal is to connect such a device to the Mogul directly via the USB connector so that it looks like a keyboard OR connect the device to an external Bluetooth transmitter that looks like a Bluetooth keyboard.
Off the self product would be preferable to having to black box the project.
It would seem simple considering there are USB Bluetooth transmitters at fairly low cost, but I have not been able to find one for this specific application. Hacking and existing Bluetooth keyboard might work but it would be a bulky solution, a considerable downside as well as expense for each of the devices.
I'm not a corporate Mogul, just a single employee company / end user who has specific data collection needs.
Thanks in advance
Hey friends, i'm starting to work with microcontrollers, i'm absolute newbie, and I want to ask what does UART and JTAG means? Explain as simple as possible! Thank you so much!
UART = Universal Asyncronous Receiver/Transmitter
JTAG = Joint Test Action Group
UART is a type of chip that controls communications to and from a device, such as a microcontroller, ROM, RAM, etc. Most of the time, it's a serial connection that allows us to communication to a device.
JTAG is a set of test ports that is used for debugging but can also be used to program firmware (which is commonly done).
I'm working to develop an application to use a rooted Nook STR as a handheld data input platform, which then sends the data to another Android device (tablet or phone; TBD) acting as a hub. From what I've been able to determine, the options for communications between the devices are:
Bluetooth
-Possibly available using a dongle, USB OTG cable, and enabling USB host mode as described here. This doesn't seem practical within the time/budget/scale of our application.
Wi-Fi
-Wi-Fi Direct would be ideal, but requires either Android 4.x or a patch/hack to enable it, which I haven't seen anyone working on (correct me if I'm wrong about this)
-Separate Wi-Fi hub to manage communications between the devices
Is there an alternative, implementable within reasonable time and cost, to facilitate device-to-device communications wirelessly and without additional separate hardware? My research hasn't turned up any solutions that aren't extremely awkward, but I'm relatively new to this, so hopefully someone has a better idea or knows of an obvious possibility that I'm missing.