How to read from USB without any driver?

We are creating small system which has GPS receiver and PC. We want to test my GPS receiver, We do not want to go for a driver on the first go. First I would like to test my circuit works or nor. GPS IC has been set to output NMEA sent开发者_高级运维ence. We want a program which just reads data from USB port and print it on the screen.

Can we write something like this easily ? Do we have any open source tool which will achieve this purpose ?

Platform : Windows 7

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All devices need a driver, so I'm going to interpret your question as "how can I read NMEA data from my GPS using only drivers provided by the OS, so I don't have to write my own?"

If the GPS chip has a USB interface, then you should have gotten a driver with it. But most GPS chips have a UART interface which in your case sounds like it is connected to a separate USB-UART conversion chip. That conversion chip most likely came with a driver as well, but if not, you could jumper the reset pin of the converter chip, disabling it, and then attach a TTL/RS-232 level converter (available off-the-shelf) to the UART traces and then to your computer's serial port.

Unless you suspect that the driver for the USB-UART converter is causing problems, I wouldn't bother.

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Anything connected via USB is a device. Devices require a device driver, period.

You might be able to get away with an existing driver built into Windows. This is how USB memory keys work for example - they present a generic device that looks like a removable disk, and Windows already includes the drivers for generic removable disks.

You would need to check the documentation for your device to see if it can emulate a device which already has drivers. Otherwise you must install the company's drivers, or you're out of luck.

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Have a look at libusb. You should be able to read the data with that and a little code. (Yes, it's a driver. I take the question to mean "without writing a driver".)

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You need a device driver for your device. Unless Windows already have a class driver for the device.

For USB devices on Windows 7 you can write a user-mode driver, see UMDF.