--3MwIy2ne0vdjdPXF
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hi,

On Fri, Nov 01, 2002 at 08:02:50AM -0600, Peter Seebach wrote:
> So, I managed to get a terminal - an old WYSE 160.  It mostly works pretty
> well as a serial port gizmo, with a couple of problems.
>=20
> 1.  The terminal doesn't appear to support CTS/RTS handshaking; it suppor=
ts
> DSR/DTR.  (Either that, or this is a DCE/DTE line naming convention thing,
> and it *should* work, but...)

etc.

Maybe it's wired according to the old-fashined line names?

As seen from the DTE:

- RTS requests that the DCE makes itself send-ready, and CTS
  tells the DTE that it may send.

- DTR tells the DCE that the DTE is ready.

Hmmmmmm - found a Wyse-85 handbook. Lets see:

yes, it does DTR.

Table 2-8 communications tow setup parameter
Parameter	& Settings	& Explanation\\
Handshake	& XOFF		& Terminal sets XOFF to stop data being=20
				  received, and sends xon when it is ready
				  to receive again.
				  Terminal also stops sending data when an
				  XOFF character is received from the=20
				  computer and resumes sending data when an
				  XON is received.

		& DTR		& Terminal lowers the DTR (data transmit) line
				  (Pin 20) to stop data being received on the
				  COMM port, and raises the DTR line when
				  it isready to receive data again.
				  XON/XOFF characters recieved by the terminal
				  on the COMM port are ignored.

There are also BOTH and NONE modes.

Furthermore, if the Parameter "Port" is set to "EIA Modem", according to
Appendix B, Table B-1, data is sent by the terminal if CTS (5), DCD (8) and
DSR(6) are high.

So to communicate with a new-ish serial port, your null-modem cable needs
to be wired similar to this:

T =3D Terminal, C =3D Computer (assuming 25pin)

T7 - C7		Signal ground

T2 - C3		Terminal data -> Computer data
T3 - C2		Terminal data <- Computer data

T20 - C5	Terminal ready -> Computer "clear to send"
		probably also tie this to C8 and maybe C6

T5 - C4		Terminal clear to send <- Computer "request to send"

also, tie T6 and T8 to this.


I had to do half of this to connect real serial printers to SunOS boxen
back then when I was younger.


Regards,
	-is

--3MwIy2ne0vdjdPXF
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.6 (NetBSD)
Comment: For info see http://www.gnupg.org

iD8DBQE9wpfvPCRcZ/VMtk4RAlv7AJ9PNDjWYS7cIFbd9lRUWOPjsjUyigCeMct6
VzS+4QC26EugoTzIFphRjVc=
=doGS
-----END PGP SIGNATURE-----

--3MwIy2ne0vdjdPXF--