Robert Polding

Hi,

I've recently started a project developing an application for a PDA that
reads RFID tags (tags that emit a radio signal containing a unique id
number, and that can be picked up by a reader). I have been supplied
with a reader and tags but unfortunately very little information on how
to actually program it. All I've been told is:

This reader has a standard CF interface. To get the bits into your PC or
PDA, you must use the same part of your development system as for
reading other data from a CF card. The meaning of the bits you can find
in John's e-mail. Please do not forget that different processors might
need different versions.

The email they're referring to contains the following information:


Data format for reading the tags is as follows:
STX(1BYTE), RFID_ID(4BYTE) totally 5 ASCII characters
STX is 0x02h
RFID_ID include 4 bytes, representing a 2 bytes unsigned integer,
such as ID=10811, the hexadecimal expression will be 0x2Ah, 0x3Bh
while it can be expressed as 4 bytes ASCII characters: 2, A, 3, B.
Therefore, the data PC received for a tag with ID=10811 is :
Expression in ASCII : STX 2 A 3 B
Expression in hexadecimal: 0x02h 0x32h 0x41h 0x33h 0x42h
Starting with 0X02h, the following 4 bytes represent an ID number.

Can anyone please help as I cannot understand this. I need to be able to
read a value into a variable, using VB.NET, but have no idea how to do this.

Thanks for your time.

Robert Polding
The University of Sheffield


Re: .NET Compact Framework Require help accessing CF RFid Reader in Compact Framework

Ilya Tumanov

This description contains no information on how to read the values, only vague description on what these values are.

You should contact reader manufacturer for manual, drivers/SDK (unless it uses standard driver like serial port), without these this device is completely useless.






Re: .NET Compact Framework Require help accessing CF RFid Reader in Compact Framework

Robert Polding

Thanks for your reply. We've been in touch with the manufacturer and they state that "the CF interface is used as a serial IO like an RS-232". They have also provided a driver for Windows, at least this is what I think it is. There are several files and no instructions, these are:

OXSER.INF
OXSER.SYS
OXUI.DLL
修改(modify)COM序 (serial number).txt

The text file states (I had a colleague explain the meaning of the Chinese, shown in brackets):

名 : (item name) HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96D-E325-11CE-BFC1-08002BE10318}\0008

值 (value) 0
名 : (name) AttachedTo
型: (category) REG_SZ
据: (data) COM4

They also included an image of the driver working in Windows, does this mean the driver is not compatible with the PDA, and is only a Windows driver

FYI the PDA I'm using is a Dell Axim with an
Intel XScale processor.

I've still not got much closer to actually using this information, and have contacted the supplier for more information on how to use the driver and access the data. Can anyone please tell me if it is easy to access the
serial IO mentioned above, preferably in VB/C#




Re: .NET Compact Framework Require help accessing CF RFid Reader in Compact Framework

Ilya Tumanov

Yes, it appears to be a driver for desktop, not for device. It's just as useful on device as gasoline if you running low on diesel.

You’re not going to get any closer until you get a driver for your device, whatever you get it from manufacturer or write it yourself (C++ required).

After that you would get a extra serial port which you can access using SerialPort class in NETCF V2.

The best way for you to go is to drop this scanner and purchase one with device drivers instead.






Re: .NET Compact Framework Require help accessing CF RFid Reader in Compact Framework

Robert Polding

Thanks, I've found out how to access the reader now, it just uses the serial port. In case anyone else uses it, it's a SMPD-100 from Synometrix, and doesn't hardly have any documentation. The port is Com4 and baud rate 19200.