[OT] sparc-->mac serial cable

[Hugh Saunders <hugh@mjr.org>]

Hello, i am attempting to build a serial cable so i can use an old mac
laptop [powerbook510] to boot a sun sparc ipc and start it network booting. 
Google reveals the following pinouts:

AppleMac [1]
DIN8		Signal	Description
Pin
----------------------------------
1				RTS			Handshake output
2				CTS			Handshake input
3				TXD-		Transmit data (inverted)
4				SG			GND
5				RXD-		Receive data (inverted)
6				TXD+ 		Transmit data
7				DCD			General Purpose Input
8				RXD+		Receive data

Sparc IPC [2]
DIN8    Signal  Description
Pin 
----------------------------------
1       DTR     Data Terminal Ready
2       CTS     Clear to Send
3       TXD     Transmit Data
4       GND     Ground
5       RXD     Receive Data
6       RTS     Request to Send
7       DCD     Data Carrier Detect
8       RTXC    Receive Clock

My first question is: how do i wire it? do i try and match the pins up ie
RTS-->RTS or do i cross over as in RTS-->CTS?

Next question, whats with TXD[+-] on the mac but only TXD on the sparc? can
i just use TXD+ -->TXD? [or TXD+ -->RXD if crossed over] then ignore
TXD-?

The weak debian link is that it will [if i ever get it booted]
be a debian box :-)

thanks,

hugh

Datafrom:
[1]http://62.194.125.41:8080/pinouts/mac_pc_serial.html
[2]http://www.stokely.com/unix.serial.port.resources/A-B-Ycablepinout.html#ipc.ipx.link