PictureTel III ISA manual To make a crossover cable, connect TD+ to RD+ and TD- to RD

C-2APPENDIX C: CROSSOVER CABLE TROUBLESHOOTING TIPS

2To make a crossover cable, connect TD+ to RD+ and TD– to RD–.

The cable performs the crossover that is usually performed by the

hub. Figure C-1 shows the pinouts for the crossover cable:

.

12345678

	Straight-through				Crossover
	10BASE-T cable				10BASE-T cable
1		1	TD+ 1		1	TD+
2		2	TD	2	2	TD
3		3	RD+ 3		3	RD+
4		4		4	4
5		5	RD	5	5	RD
6		6		6	6
7		7		7	7
8		8		8	8

Figure C-1Straight-Through and Crossover Cable Pinouts

If the file server and client PC function together as a small network, then either the existing cabling or the hub is failing.

■With a correct crossover connection, the LED lights.

■With a straight-through connection, the LED does not light.

■With a polarity mismatch (that is, TD+ to RD– instead of TD+ to RD+), the LED blinks.