ALARM/STATUS

RS232

Chapter 3 Features and Functions

Outputs

ALARM/STATUS Port

This DE-9P (male) subminiature D connector or port allows you to monitor the status of the 58502A via pins 2, 3, and 4 (see Table 3-1). This port also allows you to receive compatible BITE (Built In Test Equipment) alarm inputs from the 58503A GPS Time and Frequency Reference Receiver and the HP 5071A Primary Frequency Standard via pins 6 and 7.

The pin assignments are described in Table 3-1.

Table 3-1. ALARM/STATUS Port Pin Assignments

Pin

Signal

Description

Number

 

 

 

 

 

1, 5, 9

GROUND

Signal return, ground potential.

 

 

 

2, 3, 4

ALARMS OUT

TTL

 

 

 

6, 7

ALARMS IN

TTL

 

 

 

8

________________

Do not use or ground.

 

 

 

See the section “Different Ways to Check Alarm Status,” which discusses three different ways you can check the alarm status of the 58502A.

ALARM/STATUS Port Outputs

The output pins (2, 3, and 4) of this port, shown in Figure 3-1, allow you to monitor the status of the 58502A. Output pins 2, 3, and 4 are a TTL high (3.5 Vdc, minimum) when operation is normal, and TTL low (1.5 Vdc, maximum) if there is an alarm.

Alarm Outputs

ALARM/STATUS

1 2 3 4 5

6 7 8 9

Figure 3-1. Alarm Outputs

All of the output pins are at a TTL high when there is no alarm condition. When an alarm condition exists, all of the output pins drop to a TTL low. These outputs echo the state of front-panel Alarm indicator.

3-4

User’s Guide