New subject: NeXT hardware issue (was: mac serial pinouts)

9 Oct 2000

Larry Walker wrote:

...
  I've also got a NEXT which IIRC uses RS423 prot.
but has a
similiar miniDIN. These guys really keep the cable manufacturers
busy.  Again the specs are hard to find. Is there such a thing as a
repositry of cable connection specs ? 
Ooooh ooooh! I can help! A quick cut, paste, ftp, and addition of a little
ascii art later, here, almost straight from the on-line copy of the System
Admin's manual on my NeXT running NeXTStep 3.3 are:

NeXT Computer Serial Ports

Serial ports A and B use 8-pin miniature DIN (MiniDIN-8) connectors. Both
ports on a 68040-based NeXT computer are RS-423 compatible; the ports on a
68030-based NeXT computer are RS-422 compatible (though different). The
following diagram and table describe the pin configuration of each port:

         8  7  6
        5    4  3
          2   1        (ed. drawing makes each location look like a
                        socket, not a pin, as would be found on the
                        back side of the computer. That matches my '040 Cube.)

Pin	Signal			Pin	Signal
	1	DTR			5	RXD
	2	DCD			6	RTS
	3	TXD			7	RTXC
	4	GND			8	CTS

NeXT-to-Modem Cable (MiniDIN-8 to DB-25)

The following table describes the configuration of a cable used to connect
a 68040-based NeXT computer to an asynchronous modem. This configuration
supports RTS/CTS hardware flow control.

MiniDIN-8	DB-25
Pin	Signal	Pin	Signal
1	DTR	20	DTR
2	DCD	8	DCD
3	TXD	2	TXD
4	GND	7	GND
5	RXD	3	RXD
6	RTS	4	RTS
7		(Not connected)
8	CTS	5	CTS

NeXT Null-Modem Cable (MiniDIN-8 to DB-25)

The following table describes the configuration of a null-modem style cable
used to connect a terminal, printer, or other computer to a NeXT computer.
This configuration supports RTS/CTS hardware flow control.

MiniDIN-8	RS-232
Pin	Signal	Pin	Signal
1	DTR	8	DCD
2	DCD	20	DTR
3	TXD	3	RXD
4	GND	7	GND
5	RXD	2	TXD
6	RTS	5	CTS
7		(Not connected)
8	CTS	4	RTS

NeXT Null-Modem Cable (MiniDIN-8 to MiniDIN-8)

The following table describes the configuration of a null-modem style cable
used to connect two 68040-based NeXT computers. This configuration supports
RTS/CTS hardware flow control.

MiniDIN-8	MiniDIN-8
Pin	Signal	Pin	Signal
1	DTR	2	DCD
2	DCD	1	DTR
3	TXD	5	RXD
4	GND	4	GND
5	RXD	3	TXD
6	RTS	8	CTS
7		(Not connected)
8	CTS	6	RTS

NeXT Null-Modem Cable (DTR Flow Control)

The following table describes the configuration of a null-modem cable used
to connect a NeXT computer to a printer that only supports DTR hardware
flow control, rather than RTS/CTS hardware flow control.

MiniDIN-8		RS-232
Pin	Signal	Pin	Signal
1	DTR	8	DCD
2	DCD	5 	CTS
3	TXD	3	RXD
4	GND	7	GND
5	RXD	2	TXD
6	RTS	20	 DTR
7		(Not connected)
8	CTS	4	RTS

Heck of a time to ask, but NeXTs are on-topic now right? Right? I hope? The
copyright on the back of my box says (c)1989.
								- Mark