You don't say what type of serial card you are using. With most serial cards you have a separate tty device to describe the printer. For example , one equinox board generates ttyiac for a terminal and ttyiaclp for the printer device. You would use /dev/ttyiaclp as the port for the printer. Built into the device is the code to turn the terminal display off/on and the printer on/off. There should also be a serial card setup utility that will allow you to set the ttytype which changes the print on/off code.
Lacking these tools, or using standard ports, you can create a new printer model and include the printer on/off codes around the portion of the code that actually outputs the file to the ttydevice. You could also do the same thing in the printer interface script but it is a better practice to do it in models.
And failure to match the ttytype to the terminal will also create this problem.
Sorry this is so long. Ed Fair
efair@atlnet.com
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