How to sense a printer's paused/off-line state ?

[saytamaner]

Hello,

I use dot-matrix printers (Epson LX-300) connected to Windows CE
devices via serial port, for my application's printing needs. Using
both OpenNETCF's serial comm classes and Windows CE API functions, I
had no problem with printing or determining whether printer is turned
on. But I couldn't find a way to check the printer's paused/off-line
state (it is turned on but set off-line via front-panel button).

Even if it is paused, the printer still accepts and stores the data in
the buffer and prints it when it is set on-line again. But if it is
turned off while it holds the data in the buffer, the print job gets
lost. That's why I don't want to send data while the printer is paused.
So I need the application to warn the user to set the printer on-line,
like it warns when the printer is turned off.

Does anybody know how to accomplish this ?
Any possibility of a serial line goes on/off when the printer is paused
?

Thanks in advance and best regards.

 

[ackesa]

Hello,

I'm Printing via USB, But If the printer is powerd-off, i get exception
when I'm trying to connect to the printer. On the Serial Port it should
be the same:
If you want to know, which printer is powered-On, try to connect to
them. If you don't receive an exception, the printer on.

Regards,
Sabine

 

[saytamaner]

Hello,

I'm Printing via USB, But If the printer is powerd-off, i get exception
when I'm trying to connect to the printer. On the Serial Port it should
be the same:
If you want to know, which printer is powered-On, try to connect to
them. If you don't receive an exception, the printer on.

Regards,
Sabine

Thanks for your reply.
I can determine if the printer is powered on by checking CTS line of
the serial cable.
What I need is to be able to sense whether it is paused or not (via the
front panel
pause button).

Regards,
Serdar

 

[Paul G. Tobey [eMVP]]

That would depend on the printer. There are too many "ifs" to list, but it
might be pulling one of the handshake lines (or not), or it might send an
XOFF if you send it some characters (or not), or it might never tell you at
all that it's paused. It's the printer that decides that. Maybe there's
even a control code that you can send to which it will reply to indicate
that it's paused (again, or not). You'll have to read the technical manual
for the specific target printer.

Paul T.