6.4.7 HELP and Error Recovery

a)

If the prompt is OBST> and you have forgotten the name of a VERB, or what a VERB does, type,

OBST>

HELP
to see a list of OBST and SIC commands.

OBST>

HELP OBST\
gives you a one-line explanation for all VERBS and some general explanations in OBST.

OBST>

HELP <verb>
gives you the OBST command line for the VERB with all its related ADVERBS and some additional information.

OBST>

HELP <verb> /<adverb>
gives further information about the ADVERB. For example:

OBST.

HELP C_MODE

   Defines parameters for the C (ontinuum) observing mode
       
	       C_MODE       [<configuration>]
			    [/PHASES_C <nr_of_phases>]
                            [/RECEIVER_C <rx_nr>]
			    [/CYCLETIME_C <phase_t> <blank_t>]
			    [/FREQUENCY_C <freq> [unit]  <sideband>]
			    [/BACKEND_C <backend_ID>]

Examples:
  C_MODE T /FREQ 230. Ghz
    Set the total-power configuration for continuum to the latest
    default values and a new default frequency of 230. GHz.
														
  C_MODE B
    Set the backend up for beam-switched observations.

Warning:

    The parameters set by this command become the new default values.

Additional information available:
<configuration>:      /PHASES_C  /RECEIVER_C           /CYCLETIME_C
/FREQUENCY_C          /BACKEND_C /SWITCHES_C

OBST>

SHOW_CURRENT <verb or adverb>
is to be used should you just want to see which parameters are being used currently. You have to give enough characters for the name of the VERB or ADVERB that a minimum match is unambiguously. In case of too few characters all possible candidates are listed, so you can repeat the input with a sufficient number of characters. For example, 'SHOW POI':

              Current                        Default
 $POINTING    TOT                            TOT
 LENGTH_PT    180                            180
 TIME_PT      30                             30
 SUB_PT       4                              4
              ONE_COORD                      ONE_COORD
ORIENTATION  ELEVATION                      ELEVATION
				  
 $PRASTER     2700                           2700
	      0                              0
	      BASIS                          BASIS
	      ORIG                           ORIG
 MAPSIZE      480                            480
              10                             10
	      360                            360
	      10                             10
	      AZM                            AZM
 TIME_L       30                             30
              30                             30
 ON_OFFS      1                              1
              NO                             NO

b)

If you receive the reverse-video prompt while executing a command procedure: During the execution of a VERB, or one of your own observing procedures, an erroneous command line can occur. The program then returns with a reverse-video prompt containing the level number, e.g. OBST_3>. If you cannot correct the problem and continue using the SIC CONTINUE command, then erase the incorrect line after the prompt and enter QUIT. Repeat QUIT until you get the normal video OBST> prompt and correct the procedure by editing (using a SIC DCL command to go to DCL), or replace the incorrect parameter.

c)

Inside a FOR loop, after CANCELling or KILLing an observation: In the start up, OBST receives a SIC error recovery ON ERROR PAUSE. In the case of a fault occurring, this command returns control to you as the interactive user, when you are executing a command procedure. KILL or an operator intervention during the execution of an observation (no OBST> prompt) will set the error flag, and SIC prompts with its current execution level, e.g. OBST_4>. Input QUITs until you reach the regular OBST> prompt. If you wish to complete the execution of the loop, enter CONTINUE for the loop to continue the execution with the next command in the loop. CANCEL will terminate the current observation, but will continue the command procedure, as will KILL followed by CONTINUE.

d)

If there is no OBST> prompt: If there is no prompt, you are most probably in the WAIT state, the command has to wait until the previous observation is finished. Look at the messages in the upper right part of the display. In the upper left part OBSERVE informs which subscan is currently executed. If you want to cancel the current observation, you have to enter a <CTRL-C> and then type either KILL, CANCEL or CANCEL S. If you don't type one of these 3 commands, the current observation will continue, but the next one does not start until you repeat the command. Section 6.9 contains a full list of VERBS and their related ADVERBS.