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The parallel port, Parallel port – Telos ZephyrExpress User Manual

Page 141

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8-12 SYSTEM FUNCTIONS

The Parallel Port

ZephyrExpress’ parallel port has five contact-closure outputs and four logic or contact-
closure inputs. Voltages and connection details are in Section 3, Hardware.

Parallel Port

PIN

FUNCTION

PIN

FUNCTION

1

Ground

9

N/C

2

Output 2

10

Output 0

3

Status Out

11

Output 1

4

Output 3

12

N/C

5

N/C

13

Input 2

6

Input 3

14

Input 1

7

Input 0/Panic Dial

15

N/C

8

+5 volts 400 ma max.

One of the five outputs, pin 3, is used to report successful connections. Use the

Codec:

Status Out

menu item to set this pin to go active low when the receive decoder is locked,

or when either or both lines are connected.

One of the four inputs, pin 7, can be used to initiate “Panic Dial” and call a particular
number when it’s pulled low. Use the

ISDN: Panic dial

menu item to specify an autodial

setup, which can also include a master setup that configures the codec or other menus.
If no Panic Dial setup is specified, the input can be used for ancillary data.

i

ISDN TIP!

Panic Dial calls stay connected only while pin 7 is low. When pin 7 is lifted from
ground, the call is dropped.