Setting up RFID reader.

The Senor sample RFID reader we have came with the iSPOS series of touch screen computers.  In these systems the com ports are set up as follows:

 * Com1: Integrated Customer display
 * Com2: Touch screen
 * Com3: RFID Reader
 * Com4: Available for use
 * Com5: Integrated 40 Column docket printer
 * Com6: Available for use
Since in Linux the default kernel behavior is to only support 4 serial ports, we have set up the following:

 * /dev/ttyS0 Integrated Customer display
 * /dev/ttyS1 Touch screen
 * /dev/ttyS2 Integrated 40 Column docket printer
 * /dev/ttyS3 RFID Reader
=== In order to communicate with the RFID reader, we need to send it an initialise command (this will cause the device to beep): ===
{{{
send      01 03
response  01 01
send      01 03
response  01 01
send      02 0b 0f
response  01 00
}}}
=== Once the device is initialised you need to continously poll the device with the Search Card command: ===
{{{
send      02 02 26}}}
You will get one of the following responses:

Detected a S50 type tag

{{{
response  03 00 04 00
}}}
Detected a S70 type tag

{{{
response  03 00 02 00}}}
No card detected

{{{
response  01 01}}}
=== If you detected a tag, you need to send it an Anticollision command to read its serial number: ===
{{{
send      01 03
response  05 00 52 00 75 7A}}}
05 00 52 00 75 7A is the tag serial number.  If you get 01 01 that means the tag was taken off before we could read it.
We will capture this serial number and assign it to an operator.