Communications Interface

RS232 Serial Communications Interface

The RS232 Serial interface connector is a 14 position Molex Minifit Jr®., part number 39-30-1140, which mates with Molex part number 39-01-2140 or equivalent.

Signal Voltage and Current levels

The serial interface meets EIA RS232 interface specifications:

Voltage Levels Max +-15 Volts
Min +- 3 Volts
Mark = Off = -3 to –15 Volts
Space = On = +3 to +15 Volts

Note: Power may be applied through this connector or the 4 pin power connector. See the DC Power Requirements section for 24 volt power requirements.
Note: GND is the 24V return.
Note: FGND and GND are connected in the printer.

USB Interface

The USB interface supports USB Version 2.0 High speed or full speed. The standard USB interface is implemented through a standard Series “B” receptacle as defined in the USB Specification. The printer is self-powered and does not draw power from the standard type B USB interface cable.

The Standard USB Type B connector has the following pin functions:

Pin Signal
1 Vbus (+5 V dc[1]) (This is used to select between Interfaces)
2 Minus data
3 Plus data
4 Ground

Note: The standard USB interface does not have enough power to run the printer. It is not possible to power the printer with the USB cable alone.

USB Configuration

To allow the application to use a virtual serial port or a USB printer port to interact with the printer, the EPIC 880TM supports both ports, and can be configured to support a Virtual COM port or a USB Printer device. The USB section of the configuration allows USB Mode, USB Enumeration, and whether the printer will perform a normal Windows plug and play operation to be configured. The default is printer port, use description, with Windows PnP on.

You should configure these options based on how you want the printer to perform in your system. Typically only the Virtual COM or USB printer driver is required: to load the Transact Virtual COM port driver, disable the USB printer port. Typically you can use the description as the enumeration ID, representing how the printer is uniquely identified to the host. If you select a description, all Epic 880’s will be the same, and you can interchange printers without affecting the port location, subject to the limitation that no more than one Epic 880 can be connected to the same host. If that is a requirement, select ID by serial number or allow the ID number to be assigned by windows based on the connection.

You can also disable the Windows PnP sequence. This will prevent the Windows system from receiving the printer driver selection sequence. This will allow you to manually assign a driver to the USB printer connection and not have Windows keep asking for a printer driver.

The adapter will support a high speed USB interface if the host also supports high speed. If the host does not support high speed the printer will revert to full speed. It is possible to disable high speed operation by setting a configuration option. The printer does not support the USB low speed protocol.

The most reliable USB interface is as a USB printing device. The Virtual COM driver is an added layer of code that allows legacy software to believe it is interacting with a serial port. Note that a limitation of serial communications port virtualization is that each version of windows is slightly different, and not all RS232 features are supported: only features such as receive, transmit and ready/busy are supported, while other features such as on hook, off hook, ring, and break are not supported.

Power connector

Note: Power may be applied through the 14 pin connector. See the Communications Interface section for more information.
Note: The 24V RTN and FRAME pins are connected inside the printer.

Frame Ground Requirements

An adequate frame ground is required for this product to meet the required ESD immunity standards. It is expected that a typical installation mounts this printer to a metal chassis that is the system “frame” or “safety” ground. This ground must provide adequate conductivity to provide ESD immunity. In cases where the chassis is not connected to the system “frame” or “safety” ground, it is necessary to ensure the printers metal chassis is connected via a separate ground strap with suitably low impedance. It is up to the system integrator to provide adequate frame grounding.

Test Standards

CE MARK (1998)
EN 60950-1
IEC 60950 (1991) Second Edition with Amendments 1,2,3,4

Acoustic Noise:

58 dbA average (sound pressure level) while printing a rolling ASCII format. Microphone positions are at 10 different positions spaced around the printer as defined in ISO 779.