Questions about types of printer interfaces are pretty common for me, so I thought I’d write an informative blog for all of you looking for clarification.  Although I specify receipt printers, this post applies to all printers, including thermal barcode printers.  Just keep in mind that receipt printers, are generally limited to a single interface type, whereas larger printers often support multiple interface options.  Rather than getting into the reasons for why different interface options are used and what their place is historically, I’m going to keep this on a very basic level by identifying the each type of printer interface and providing pictures of the cables used to make the connection.
Serial Null Modem CableSerial Printer Interface  – Usually 25 pin female at the printer to a 9 pin male connection at the host computer.  The cable is obviously gendered the opposite and looks like this picture.  Receipt printers usually require a serial null modem cable, which is wired differently from a straight through cable.
parallel printer cableParallel Printer Interface – Usually 36 pin Centronics female at the printer to 25 pin female at the host.  Parallel was a very common interface for many types of printers before USB became popular.  Parallel interface is covered under the IEEE standard, which you will often see on cable packaging.
USB ABUSB Printer Interface – USB is the current de facto standard for local connection to a PC.  The connection is almost always USB Type B female (the D-shaped end) at the printer to USB Type A female (the flat end) at the host.
Cat5e RJ45Ethernet Printer Interface – Ethernet is the standard method of networking computers.  The standard connection type is RJ45 and the cable type is Cat 5 or Cat 6 twisted pair.  Ethernet printers allow you to easily share the printer with all computers on the network.  The printer will connect to a network switch or router.  Both ends of the connecting cable will look like this.
Having a certain type of receipt printer interface does not mean that you can’t switch to another type, but you will want to check with your POS (Point of Sale) Software Vendor or search through the settings to ensure that the software is capable of communication with the printer via your preferred receipt printer interface type.
As always, I encourage you to browse through our receipt printer selection and call, email or use our Live Chat feature for any questions you have before making your purchase.