USING COMMAND VERBS

To use the command verbs effectively, you need general information about their usage. Topics related to the use of command verbs, which are discussed in the following paragraphs, are as follows:

• Driver action

• Prompts and default responses

• Equi'valence file

• Diagnostic message queue 3.2.1 Driver Action

The driver activates and controls the diagnostic tasks. After initializing the tasks, the driver assumes its normal state of processing requests for services and messages for the diagnostic tasks by monitoring the diagnostic message que'ue. Any request for service from the control ter·

minal interrupts the normal activity of the driver and returns the driver to the terminal.

While at the control terminal, the driver responds to most command verbs by displaying prompts that ask for detailed information. When the prompts are displayed, the cursor also appears on the screen, indicating the field where you must enter your response. Whenever the cursor appears at the control terminal, the driver is inactive and cannot continue until you respond. This means that some diagnostic tasks may be unable to continue until the driver completes processing command verbs at the control terminal and returns to its normal state of monitoring the diagnostic message queue.

Before the driver can process your command verbs at the terminal, it must check your reponses to the prompts to be certain they are valid.

2270532-9701 3·3

3.2.2 Prompts and Default Responses

Each prompt is displayed in the form of a question that can be followed by the default response to the question. In some cases, all valid responses to the prompt are also displayed in parentheses before the question mark. If the valid responses are not displayed and you need to know what they are, you can enter the HELP command verb (if you installed the help feature) or you can refer to the appropriate section of this manual (Section 3 for command verbs, Section 5 for individual tests, or Appendix I for reference tables).

The default response to the prompt always appears after the question mark. The following exam-ple shows the prompt that appears after you have entered the name or class of the device(s) to be tested. YES and NO are the possible responses; YES is the default.

EXAMPLE

USE DEFAULT OPTIONS (YES,NO)? YES

You can either accept the default (YES) by pressing the Return key or enter NO and then press the Return key.

3.2.3 Equivalence File

All command verb prompts have a range of valid responses .. These responses correspond to numeric values in a preprogrammed table that the Online Diagnostics Driver uses. The first two columns of Table 3-2 show the contents of the preprogrammed table.

3·4

Table 3·2. Prompt Responses and Equivalents

Numeric Value

Table 3·2. Prompt Responses and Equivalents (Continued)

The driver also uses a file, the equivalence file, that contains alternate responses assigned to the same numeric values. The equivalence file is a text file named volumename.S$ODIAG.EQFILE.

You can edit this file to customize the alternate responses.

After you enter your response to a prompt, the driver searches the equivalence file for the charac-ters you entered. If the characcharac-ters are present, the driver uses the corresponding numeric value to perform the appropriate function.

If the characters are not present in the equivalence file, the driver searches the preprogrammed table for the characters. If the characters are in this table, the driver uses the corresponding numeric value to perform the appropriate function. If the characters are not present in the prepro-grammed table or the equivalence file, the following error message is written to the file or device you specified in response to the MESSAGE OUTPUT prompt of the XODD command:

ILLEGAL INPUT! INPUT

=

where:

xxxxxxxx are the characters you entered.

Because the driver searches the equivalence file first, you can customize your responses to com-mand verb prompts without affecting the Online Diagnostics software.

2270532-9701 3·5

To change the equivalence file, enter the characters of your customized response, starting in col-umn 1. On the same line, enter the numeric value of the original response from Table 3-2, starting in column 9. For example, in Table 3-2 the numeric value of the original response OPERATION is 41. To save keystrokes, you can assign a shorter response (0) to the numeric value 41 by adding it to the equivalence table.

The following example shows an equivalence file (volumename.S$ODIAG.EQFILE) that allows you to enter Y instead of YES, N instead of NO, R instead of REJ ECT, and 0 instead of OPERATION.

EXAMPLE

Y 15

N 16

R 31

o 41

3.2.4 Diagnostic Message Queue

After the driver processes a command verb from the terminal, it checks the diagnostic message queue. This queue contains messages from the diagnostic tasks that request driver action. The driver processes the messages in the order in which they are entered into the queue until you call it back to the control terminal. While the driver is monitoring the message queue, the following message appears on the screen:

ONLINE DRIVER AVAILABLE - PRESS 'COMMAND' FOR NEXT COMMAND VERB

To return the driver to the control terminal, press the Command key and wait for the command prompt to appear.

3·6

CAUTION

When the driver Is waiting 'for Input at the terminal (the cursor Is on the screen), diagnostic tasks with messages In the message queue waiting to be processed by the driver may be suspended. As long as the cursor stays on the screen, some of the diagnostic tasks may be unable to execute to completion. IF YOU MUST LEAVE THE TER·

MINAL UNATTENDED WHILE A DIAGNOSTIC SESSION IS IN PROGRESS, RETURN THE DRIVER TO ITS NORMAL STATE OF MONITORING THE MESSAGE QUEUE BY EXECUTING A CHECK MESSAGE QUEUE (CQ), A WAIT ON DIAGNOSTICS (WD), OR SHOW PROGRESS OF DIAGNOSTICS (SP) COMMAND VERB. See paragraph 3.5.5.

2270532·9701