please explain this TTL->RS422 converter

Using Arduino General Electronics
#1

this is the datasheet:
http://www.mouser.com/ds/2/256/MAX13080E-MAX13089E-86294.pdf
i use the MAX13087E
page 20 in the middle you can see what i'm using
i have 1 input of DI
and outputs of A B Y Z

is this correct? this is the right way to convert TTL to RS422 with 1 input and 4 outputs?

#2

i have 1 input of DI

Yes

and outputs of A B Y Z

No. For DI the only outputs are Y & Z.

A & B are inputs from the RS422 source whose TTL output appears on the output RO

#3

i have 1 input of DI
and outputs of A B Y Z

is this correct?

No. You only have 2 outputs (A & B) and (Z & Y). See bottom of page 19. Differential line drive requires two lines, not one line and a ground. If you're not familiar with that you should read the following before using RS422.

RS422 is 5V differential line drive. The outputs on page 21 are either A & B OR Z & Y (as Mike stated).

Unlike TTL, the signal is transferred on TWO wires, not ONE. A & B is the signal names for a single driver. The one on page 21 appears to be digital switched 1-to -2 adaptor. Only one can be active at a time.

#4