Andrea Arcangeli (andrea@e-mind.com)
Thu, 21 Jan 1999 12:12:40 +0100 (CET)
On Thu, 21 Jan 1999, Tim Waugh wrote:
> > > fudge delay needs to be longer to accommodate your printer as well.
> >
> > The error signal seems to be logical and _not_ timing related.
>
> Presumably you tried altering the delay before deducing that?
As just said yes.
> 2) Waiting for a timeout to find out that the device has finished should not
> be needed.
Ok, understood. Make tons of sense from a sane handshake point of view ;)
> > > > root@laser:/home/andrea# cat /dev/lp0
> > ?MFG:EPSON;CMD:ESCPL2,BDC,D4;MDL:Stylus COLOR 740;CLS:PRINTER;
> >
> > It change when something change in the printer.
>
> The device ID changes? Interesting indeed. Which fields change - the
> manufacturer, command set, model number or device class? Personally I think
> that _any_ of those fields changing would be a neat trick.
I don't know which is the device ID field... I'll try something this
afternoon.
> > I know how to make the code working though ;).
>
> When you say that it works, is this with a timeout determining when to stop?
Yes. The timeout tell the driver when there's no more data available from
the printer. Ugly ;)
> > It has to become acceptable or I should do more reverse engeneering to
> > understand what the ERROR line means here and how could I make it working
> > here too
>
> I'll take the second option, if you don't mind.
What do you mean with `mind'?
> > But I don't have the real specs, so I couldn't know if the data-ready
> > indication was an hack as the Canon one. See things from my
> > point of view
> > ;).
>
> Did it look like a hack?
No at a first look, but I was not sure because my specs on the web told
everything of the nibble mode according to your code _except_ the ERROR
check to know when there's not data anymore. Maybe because the guy that
wrote the spces did reverse engeneering of the protocol of an Epson
printer? ;).
Please take a look at the specs I am looking at (just to see that I am not
crazy ;):
This for the nibble mode:
http://www.fapo.com/nibble.htm
This for the negotiation:
http://www.fapo.com/negoti8.htm
Andrea Arcangeli
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This archive was generated by hypermail 2.0b3 on Thu 21 Jan 1999 - 06:13:16 EST