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USB cannot read barcode scanner

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  • User profile image
    jellylychee

    Hello everyone. I wish someone would take time to read and help me with my problem. You see, I have a barcode scanner. Now, the scanner that I have has a serial port. When I connect it to the serial port on my desktop, it is working fine. The problem is, I have to do the programming part in my laptop. My laptop does not have any serial ports, so I purchased a connector that will convert it to usb. I tested the connector in the desktop, all ps/2 devices (ex. mouse) works fine. But when it comes to the barcode scanner, the computer cannot read the device. Which is weird. It can read the device when I connect it to the serial port, but it does not read the device when I connect it to the USB via a connector or converter. Sad Any ideas?

  • User profile image
    figuerres

    jellylychee wrote:
    Hello everyone. I wish someone would take time to read and help me with my problem. You see, I have a barcode scanner. Now, the scanner that I have has a serial port. When I connect it to the serial port on my desktop, it is working fine. The problem is, I have to do the programming part in my laptop. My laptop does not have any serial ports, so I purchased a connector that will convert it to usb. I tested the connector in the desktop, all ps/2 devices (ex. mouse) works fine. But when it comes to the barcode scanner, the computer cannot read the device. Which is weird. It can read the device when I connect it to the serial port, but it does not read the device when I connect it to the USB via a connector or converter. Sad Any ideas?


    some devices just do not work via the USB converters.

    I have seen paralel printers for Point of Sale apps not work via USB/Paralel adpaters for example.

    the Serial barcode reader/scanner may require a "real" serial port.

    does this have a driver in the OS when you set it up?
    or is it just a raw Serial like an old Modem ?
    can you get a USB scanner from the same Mfg ??

    new PC's are not having serial ports so I would work on moving to USB .... in the end I think it's worth it.

    9pin and 25pin Serial is just about gone.
    and really USB is a 4 wire serial buss anyway...

  • User profile image
    jellylychee

    figuerres wrote:
    

    some devices just do not work via the USB converters.

    I have seen paralel printers for Point of Sale apps not work via USB/Paralel adpaters for example.

    the Serial barcode reader/scanner may require a "real" serial port.

    does this have a driver in the OS when you set it up?
    or is it just a raw Serial like an old Modem ?
    can you get a USB scanner from the same Mfg ??

    new PC's are not having serial ports so I would work on moving to USB .... in the end I think it's worth it.

    9pin and 25pin Serial is just about gone.
    and really USB is a 4 wire serial buss anyway...


    The scanner has a 6pin male and female connector. It did not come with a driver. I just borrowed it from my school for my thesis. They do not have a USB scanner sad to say.

    So it is safe to say that the problem is with my converter? Should I try to look for other converters? Or it is just a waste of time? I read that some barcodes work when using converters.

  • User profile image
    Matthew van Eerde

    Why not get a USB barcode scanner?

  • User profile image
    jellylychee

    Matthew van Eerde wrote:
    Why not get a USB barcode scanner?


    Getting a new USB barcode scanner is my last resort. It is kinda expensive. I am still a student so.. Sad But if there is no other way, I have no choice.

  • User profile image
    figuerres

    jellylychee wrote:
    
    figuerres wrote:
    

    some devices just do not work via the USB converters.

    I have seen paralel printers for Point of Sale apps not work via USB/Paralel adpaters for example.

    the Serial barcode reader/scanner may require a "real" serial port.

    does this have a driver in the OS when you set it up?
    or is it just a raw Serial like an old Modem ?
    can you get a USB scanner from the same Mfg ??

    new PC's are not having serial ports so I would work on moving to USB .... in the end I think it's worth it.

    9pin and 25pin Serial is just about gone.
    and really USB is a 4 wire serial buss anyway...


    The scanner has a 6pin male and female connector. It did not come with a driver. I just borrowed it from my school for my thesis. They do not have a USB scanner sad to say.

    So it is safe to say that the problem is with my converter? Should I try to look for other converters? Or it is just a waste of time? I read that some barcodes work when using converters.


    probably not gonna work is my guess.

    but let's make sure you have the right things...

    you say it has a 6 pin connector?

    do you mean a round one like a PS/2 Keyboard ??

    are you sure it's not a PS/2 keyboard wedge type??
    they are common and are not a "Serial Port"

    or perhaps a Mac Serial Port device?
    some Mac's used to have a round Serial port thing.

    PC Serial ports are shaped kind of like a "D" and have 9 pins not six.

    depending on the hardware a serial port can use 2 wires,3 wires 4 wires most of the time they use 4 pins for "full duplex"
    2 or 3 for a "Simplex" connection.
    they may also cross some lines to make them "Always Ready"
    some of the old Serial wires were named:

    Clear to Send
    Ready to Send
    Data Set Ready

    they did the "Handshaking" so that one side did not just "dump" on theother when it was not ready.

    and then you had
    Transmit
    and
    Recive

    and Ground

    but most of the time they only used 3 wires for small stuff like a scaner.

  • User profile image
    figuerres

    jellylychee wrote:
    
    Matthew van Eerde wrote:
    Why not get a USB barcode scanner?


    Getting a new USB barcode scanner is my last resort. It is kinda expensive. I am still a student so.. Sad But if there is no other way, I have no choice.


    what do you need to scan?

    can you get access to a cheap all-in-one printer that can scan a page?

    you *might* be able to scan from the page and hack soem code to read the bars, if it's a std. barcode they are not that hard to work out.

    I do not know of any free libraries to read them but if you only need to read one format you can read the spec's on line for that format.

    if it's school project you could try looking up the company that made that scanner and ask them for a new one... they just might go for it.

    can't hurt to ask.

  • User profile image
    ZippyV

    figuerres wrote:
    9pin and 25pin Serial is just about gone.
    and really USB is a 4 wire serial buss anyway...


    I thought so too, until I had to connect this thing to a pc.

    To the original poster: I have a usb scanner and the thing behaves just like a keyboard device. You don't really need it to see if it works with your application. With my device, every time I read a barcode it sends the characters to the control that has the cursor in it and then it sends the Enterkey code. Just find out how your scanner behaves (for example in notepad) and make sure your application can work with it.

  • User profile image
    RichardRudek

    As figuerres has said, these devices usually 'inject' their data stream as though someone had typed it in via a keyboard. So for all intents and purposes, it is a keyboard.

    But just to be sure, here are some links so you can confirm exactly what you have: [PS/2 connector]   [DE-9 connectors]

    Also, whilst the keyboard data stream is a serialised one, it's not RS-232, which is what your suggesting when you talk about serial ports - which is probably why figuerres introduced the possibity of it being an RS-232 device - I'd doubt it.


    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc.

  • User profile image
    figuerres

    RichardRudek wrote:
    As figuerres has said, these devices usually 'inject' their data stream as though someone had typed it in via a keyboard. So for all intents and purposes, it is a keyboard.

    But just to be sure, here are some links so you can confirm exactly what you have: [PS/2 connector]   [DE-9 connectors]

    Also, whilst the keyboard data stream is a serialised one, it's not RS-232, which is what your suggesting when you talk about serial ports - which is probably why figuerres introduced the possibity of it being an RS-232 device - I'd doubt it.


    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc.



    Rich,the OP said he was connect it to a serial port on his desktop.
    using a usb converter on his laptop.

  • User profile image
    figuerres

    note the OP: my edit to add some blank lines Smiley

    jellylychee wrote:
    Hello everyone. I wish someone would take time to read and help me with my problem. You see, I have a barcode scanner.

    Now, the scanner that I have has a serial port.


    When I connect it to the serial port on my desktop, it is working fine.

    The problem is, I have to do the programming part in my laptop.


    My laptop does not have any serial ports, so I purchased a connector that will convert it to usb.
     
    I tested the connector in the desktop, all ps/2 devices (ex. mouse) works fine.

    But when it comes to the barcode scanner, the computer cannot read the device.

    Which is weird.

    It can read the device when I connect it to the serial port, but it does not read the device when I connect it to the USB via a connector or converter. Sad Any ideas?

  • User profile image
    figuerres

    figuerres wrote:
    
    jellylychee wrote:
    

    The scanner has a

    6pin male and female connector.

    It did not come with a driver. I just borrowed it from my school for my thesis. They do not have a USB scanner sad to say.

    .
    .



    starting to think this is a PS/2 keyboard wedge eh?

    perhaps the OP has a PS/2 = USB adapter ??

  • User profile image
    RichardRudek

    figuerres wrote:
    
    figuerres wrote:
    
    jellylychee wrote:
    

    The scanner has a

    6pin male and female connector.

    It did not come with a driver. I just borrowed it from my school for my thesis. They do not have a USB scanner sad to say.

    .
    .



    starting to think this is a PS/2 keyboard wedge eh?

    perhaps the OP has a PS/2 = USB adapter ??



    Yes, I'd surprised if it was primarily an RS232 device: [Barcode scanners]

    Most of the ones I've seen are the keyboard-injection type devices, because that's the simplest way of doing it - no drivers necessary.

    Now the wikipedia article does mention that a few of these devices do have RS232 interfaces. But the device still needs to get it power from somewhere.

    The PS/2 interface has a 5 Volt supply, so that's the most probable source. But older, RS232-only devices typically scavenged their power from the RS232 interface itself.

    But, those devices may not be able to derive enough power from a 'non-strict' RS232 interface - RS232 is suppose to be +/- 12 Volt signaling. But a lot of 'adapters' have 'customised' this standard, using much lower voltages, or not even using negative voltages.

  • User profile image
    jellylychee

    RichardRudek wrote:
    As figuerres has said, these devices usually 'inject' their data stream as though someone had typed it in via a keyboard. So for all intents and purposes, it is a keyboard.

    But just to be sure, here are some links so you can confirm exactly what you have: [PS/2 connector]   [DE-9 connectors]

    Also, whilst the keyboard data stream is a serialised one, it's not RS-232, which is what your suggesting when you talk about serial ports - which is probably why figuerres introduced the possibity of it being an RS-232 device - I'd doubt it.


    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc.



    Hi. I am sorry I got everyone mixed up. Sad It has a ps/2 connector. It is working fine when I connect it to the ps/2 port of my desktop. It can read the barcodes and send the data to the desktop. However when I use a ps/2 usb adapter converter (my laptop doesnt have a ps/2 port), my computer does not recognize the barcode scanner anymore. The adapter converter is working fine when I tried to connect other devices like a mouse.

  • User profile image
    figuerres

    jellylychee wrote:
    
    RichardRudek wrote:
    As figuerres has said, these devices usually 'inject' their data stream as though someone had typed it in via a keyboard. So for all intents and purposes, it is a keyboard.

    But just to be sure, here are some links so you can confirm exactly what you have: [PS/2 connector]   [DE-9 connectors]

    Also, whilst the keyboard data stream is a serialised one, it's not RS-232, which is what your suggesting when you talk about serial ports - which is probably why figuerres introduced the possibity of it being an RS-232 device - I'd doubt it.


    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc.



    Hi. I am sorry I got everyone mixed up.  It has a ps/2 connector. It is working fine when I connect it to the ps/2 port of my desktop. It can read the barcodes and send the data to the desktop. However when I use a ps/2 usb adapter converter (my laptop doesnt have a ps/2 port), my computer does not recognize the barcode scanner anymore. The adapter converter is working fine when I tried to connect other devices like a mouse.


    no big.... we figured out what you had though... not bad eh?

    I used to love it when some one would ask for "A BOX OF HARD DISKS" when I worked at a computer store....
    they wanted 3.5 inch FLOPPY DISKS!
    used to show them a HARD DISK and explain that even with the plastic it was a "FLOPPY DISK" Smiley

  • User profile image
    jh71283

    I think you'll find there here in POS world, RS232 is still very alive and kicking.

    Most POS terminals can be configured to give a 5v / 12V supply out of their com ports, and for most scanners, there is also an option of an external PSU.


  • User profile image
    RichardRudek

    jellylychee wrote:
    
    RichardRudek wrote:
    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc

    I've re-quoted my earlier question.

    jellylychee wrote:
    Hi. I am sorry I got everyone mixed up.  It has a ps/2 connector. It is working fine when I connect it to the ps/2 port of my desktop. It can read the barcodes and send the data to the desktop. However when I use a ps/2 usb adapter converter (my laptop doesnt have a ps/2 port), my computer does not recognize the barcode scanner anymore. The adapter converter is working fine when I tried to connect other devices like a mouse.


    Anymore ?

    Does that mean the barcode scanner used to work on the laptop, but then stopped for some reason ?

    If so, then [read through this post] (or even the thread), and see whether it sue to bad Device manager entries. Specifically what we're looking for will be any HIDs (Human Interface Devices).

    Also, have you tried plugging in the desktop's keyboard along with the barcode scanner, like you would (I assume) with your dekstop ?


  • User profile image
    jellylychee

    RichardRudek wrote:
    
    jellylychee wrote:
    
    RichardRudek wrote:
    You'll also need to explain what you mean by doesn't work. eg  it seems to be getting no power, etc

    I've re-quoted my earlier question.



    Anymore ?

    Does that mean the barcode scanner used to work on the laptop, but then stopped for some reason ?

    If so, then [read through this post] (or even the thread), and see whether it sue to bad Device manager entries. Specifically what we're looking for will be any HIDs (Human Interface Devices).

    Also, have you tried plugging in the desktop's keyboard along with the barcode scanner, like you would (I assume) with your dekstop ?




    When I plug it in the ps/2 port, the  barcode scanner works. The barcode scanner is recognized by my computer. When the barcode scanner reads barcodes, I can see the output in my computer. I did this in my desktop.

    The problem is, I want to work on my laptop. I have to because the rest of my family uses the desktop and I always do my work (programming) in school. But my laptop does not have a ps/2 port. So what I did was purchase a ps/2 usb converter adapter.

    When I connect the barcode scanner to the converter adapter, and I connect the converter adapter to the USB port, that is where the problem begins. "USB Device Not Recognized". The converter adapter is working fine if I connect my ps/2 mouse and keyboard but it does not work when I connect the barcode scanner.

    So to summarize, it works in the ps/2 port. But it does not work thru the use of the converter adapter.

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