Trouble Shooting Guide -
Problems with Printers

The preferred method of printing is through the Linux print spooler. In this mode the Windows session does not have direct access to the parallel port, but routes the generated printable data into the Linux print spooler, which takes care of sending it to the printing device. For general instructions on how to set up Linux and Windows for this mode of printing, please see the Printing in the NeTraverse Win4Lin Terminal Server Environmrent in the User's Guide. Make sure that there is no filtering defined for the Linux printer you are using. Windows will generate printer data in the correct format required by the printer. Print filters may change the data such that the printer is unable to correctly handle it. The follwing example of a /etc/printcap entry has no filtering defined: 
lp:\
        :sd=/var/spool/lpd/lp:\
        :mx#0:\
        :lp=/dev/lp0
It specifies only the spool directory, the maximum file size and the device name to print to. There is no 'if' entry that specifies a text filter.

Some printer manufacturers will provide special installation software on a floppy disk or CD-ROM and recommend using it for printer driver installation. These installation programs may fail to install a printer driver as they generally probe the hardware, such as parallel ports or USB ports. To install printer drivers under NeTraverse Win4Lin Terminal Server please use the method described in Printing in the NeTraverse Win4Lin Terminal Server Environmrent in the User's Guide.

If you do decide to print to a parallel port via direct port attachment as described in Direct printing in the User's Guide, please note the following caveats:

In Win4Lin 1.0 direct port attachment does not support IRQ (device interrupts) and does not support DMA.
This means that if the port is set to ECP mode in the CMOS/BIOS setup, printer and scanner drivers may try to take advantage of the Extended Capabilities of the parallel port. The result is malfunctioning software. Some drivers ignore the port setting of Windows. Even if your parallel port is set to ECP mode with the Windows driver properties not showing any IRQ or DMA resources being utilized for that port, it is not a guarantee the printer manufacturer's drivers will not try to use a DMA channel anyway.

If you are experiencing problems with directly attached parallel ports, try to set your parallel port to SPP (standard) or bidirectional mode in your computer's CMOS/BIOS setup.