supporting more than ttyS*

Tom Fowle wa6ivgtf at
Sun Jun 4 02:22:41 EDT 2017

Since many parallel ports are not bidirectional, it might be hard or
impossible to support indexing on a parallel port.  I'm pretty sure the
LiteTalk synth, a doubletalk LT with parallel port, does not support
indexing on the parallel port for that reason.  There is no means of
returning data on a "printer" port.

Tom Fowle WA6IVG

On Sat, Jun 03, 2017 at 02:32:41PM +0200, Samuel Thibault wrote:
> Gregory Nowak, on ven. 02 juin 2017 17:44:51 -0700, wrote:
> > On Fri, Jun 02, 2017 at 07:56:57PM -0400, Samuel Thibault wrote:
> > > Uh. Well, probably, actually. It's a matter of writing the driver, i.e.
> > > having a documentation of the protocol and somebody to do the tests, or
> > > better, lend the hardware for testing.
> > 
> > We already have the driver, for serial anyway. The blazer uses the bns
> > driver.
> Ah, cool :)
> > It sounds from what you said like it wouldn't be straight
> > forward to open the parallel port instead of the serial port, and just
> > start writing to it.
> Yes, since /dev/lp* provide a tty interface, so the tty codebase should
> be able to use them.  That actually shows that serdev is not enough for
> all our uses, so we'll really want to use the tty interface.
> > I thought actually that using the parallel port
> > is more straight forward, since there are no parameters like baudrate,
> > stopbits, parity, and handshaking to set. Am I totally off here?
> From a tty perspective, it's just the same :)
> But yes, there are a lot less questions with a parallel port.
> Samuel
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