CR10 OVERVIEW

 

 

Instruction #

Parameter

Description

(Loc.:Entry)

(Par.#:Entry)

09: P74

 

Minimize instruction

 

01:1

One repetition

 

02:10

Output the time of the daily minimum in hours

 

 

and minutes

 

03:2

Data source is Input Storage Location 2.

The program to make the measurements and to send the desired data to Final Storage has been entered. At this point, Instruction 96 is entered to enable data transfer from Final Storage to Storage Module.

10:P96

Activate Serial Data Output.

1:71

Output Final Storage data to Storage Module.

The program is complete. The clock must now be set so that the date and time tags are correct. (Here the example reverts back to the key by key format.)

Key

Display

Explanation

*5

00:21:32

Enter *5 Mode. Clock running but not set correctly.

A

05:00

Advance to location for year.

86

05:86

Key in year (1986).

A

05:0000

Enter and advance to location for Julian day.

197

05:197

Key in Julian day.

A

05:0021

Enter and advance to location for hours and minutes (24 hr. time).

1324

05:1324

Key in hrs.:min. (1:24 PM in this example).

A

:13:24:01

Clock set and running.

*0

LOG 1

Exit *5, compile Table 1, commence logging data.

 

OV6. DATA RETRIEVAL OPTIONS

There are several options for data storage and retrieval. These options are covered in detail in Sections 2, 4, and 5. Figure OV6.1-1 summarizes the various possible methods.

Regardless of the method used, there are three general approaches to retrieving data from a datalogger.

1)On-line output of Final Storage data to a peripheral storage device. On a regular schedule, that storage device is either "milked" of its data or is brought back to the office/lab where the data is transferred to the computer. In the latter case, a "fresh" storage device is usually left in the field when the full one is taken so that data collection can continue uninterrupted.

2)Bring a storage device to the datalogger and milk all the data that has accumulated in Final Storage since the last visit.

3)Retrieve the data over some form of telecommunications link, whether it be RF, telephone, short haul modem, or satellite. This can be performed under program control or by regularly scheduled polling of the dataloggers. Campbell Scientific's TELCOM program automates this process for IBM PC/XT/AT/PS-2's and compatibles.

Regardless of which method is used, the retrieval of data from the datalogger does NOT erase those data from Final Storage. The data remain in the ring memory until:

They are written over by new data (Section 2.1) Memory is reallocated (Section 1.5)

The power to the datalogger is turned off.

Table OV6.1-1 lists the instructions used with the various methods of data retrieval.

OV-20