supporting more than ttyS*
wa6ivgtf at fastmail.fm
Wed Jun 7 21:22:56 EDT 2017
On Wed, Jun 07, 2017 at 03:58:34PM +0200, Samuel Thibault wrote:
> Okash Khawaja, on mer. 07 juin 2017 14:40:12 +0100, wrote:
> > Some synths also toggle serial control lines which I am not sure will
> > be possible or supported by default in lp.
> Well, the serial control lines don't make any sense for a parallel port.
> But there might be some parallel ports lines used for the same kind of
> signalling, manuals of these syntheses should be checked.
> > So I suggest, for the first pass we limit lp support to bns, acntsa,
> > dummy and txprt. Then we expand it to other synths based on their
> > functionality, e.g. on ltlk we disable indexing and interrogating to
> > print ROM version.
> Sounds good.
There are at least two control lines on a basic printer parallel port, an
output that is put high when the data lines have been setup, and I thiink
taken low again after a defined time. There is an input, from the external
device, that goes high when the device is busy and low again when it's ready
to receive a new character.
Sorry I've forgotten the names of these, but that's the basics.
Of course there are bidirectional parallele ports, but they get rather
complex as pins must change function as direction changes. I'd be surprised
if synths used bidirectional ports as way back they weren't common and
everybody'd have to test for them.
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