Openbravo POS/Equipment Configuration
LibrePOS Hardware Requirements 
CPU: Pentium or Compatible RAM: At least 64MB
Known working hardware 
The following hardware has been tested and found to work in LibrePOS. It is not a complete list, so if you don't find a hardware here it doesn't mean is isn't supported.
- Citizen CBM1000 and Citizen Citizen CBM1000-II
- Epson TM-T88II and Epson TM-T88III
- Epson TM-T88IV Serial under Ubuntu Linux and Windows XP
- Epson TM-U220
- Epson TM-U230 Serial
- Epson TM-T881V Parallel
- Ithaca iTherm 280
- Ithaca 500 Ink Jet Parallel
- Star TSP100 USB on Windows XP
- Star TSP600
- Posligne TRP 100 serial kubuntu
- Posligne TRP 100 USB/XP
Barcode Scanners 
- Any keyboard wedge scanner
- Epson SR-610
- Epson DM-LS121T
Touchscreens work like a mouse, so if the operating system supports it, it will be supported by LibrePOS
Receipt Printers 
If you want to use a network printer or a usb printer (in windows), use the net use command, eg: (from the command prompt)
net use lpt1 \\computerName\printerName /persistent:yes
(You can find out what your printerName is by going to windows explorer and typing in \\computerName The printer will (hopefully) come up in the list of network-available items.
Then in LibrePOS configuration, choose file and type in lpt1.
To test if your printer is well connected, issue the following commands. Change lpt1 or lp0 to whichever port you are using
echo "test" > LPT1
echo "test" > /dev/lp0
Try configuring the printer as "file" and type in lpt1 (or /dev/lp0 for linux).
Check your cable. Some serial printers require a null modem cable, a standard serial cable+null modem adapter or even some other configuration in order to work, please check your manual or contact the manufacturer. Bytes2000 has confirmed in the forums that a Standard DB9 Null modem adapter from Radio Shack that implements the "Loop back handshaking" pin configuration
To test if your printer is well connected, issue the following commands. Change com1 or ttyS0 to whichever port you are using
echo "test" > com1
echo "test" > /dev/ttyS0
If the printer prints the word "test" then you are ready to go. On LibrePOS the easiest way to use the printer is with RXTX as it is bundled with LibrePOS.
Non Epson printers may have problems with the image command as the ESC/POS standard varies a bit from different manufacturers. In particular, some CBM printers can't handle the image command. If this happens, try removing the image from the ticket.
Forum Links 
Cash drawer 
Ensure your printer can control your cash drawer. The drawer is controlled by the printer.
Barcode scanner 
Bar code scanners come in many flavors from wands to handhelds to flat beds. Scanners also have a variety of ways to attach to your PC terminal: USB, Serial, PS/2, BUS, Bluetooth.
The easiest to get working are the PS/2 model handhelds. They require NO software or configuration (typically). They plug into a keyboard port and 'key in' the UPC barcode (and usually a carraige return). The PS/2 barcode scanners work EXCELLENT with LibrePOS in the stores I have setup. This is NOT just for adding inventory, but works to key in orders...Just like any other store does.
You can pickup used barcode scanners for $5 to $50. These are adequate for reading UPC barcodes. While laser scanners support data matrix, 2D, PDF417 and other formats...why spend the money for this? If you are only working retail, you will typically be using just plain vanilla UPC barcodes. Save your money for a decent receipt printer.
The CueCat USB Port scanner works with zero configuration on Linux Fedora Core 6. The usbhid driver auto-detects and magically converts the data to numbers. Simply click in the barcode field in LibrePOS and run the scanner over a barcode. The cord is a good 6 feet long too. And, of course, the price is right when buying used.