SECTION 1. FUNCTIONAL MODES

1.1PROGRAM TABLES - *1, *2, AND *3 MODES

Data acquisition and processing functions are controlled by user-entered instructions contained in program tables. Programming can be separated into 2 tables, each having its own user-entered execution interval. A third table is available for programming subroutines which may be called by instructions in Tables 1 or 2 or by a special interrupt. The *1 and *2 Modes are used to access Tables 1 and 2. The *3 Mode is used to access Subroutine Table 3.

When a program table is first entered, the display shows the table number in the ID field and 00 in the data field. Keying an "A" will advance the editor to the execution interval. If there is an existing program in the table, keying an instruction location number prior to "A" will advance directly to the instruction (e.g., 5 will advance to the fifth instruction in the table).

1.1.1 EXECUTION INTERVAL

The execution interval is entered in units of seconds as follows:

1/64 ...1 seconds, in multiples of 1/64 (0.015625) 1 ......31.875 seconds, in multiples of 1/8 (0.125)

32 .....8191 seconds, in multiples of 1 second

Execution of the table is repeated at the rate determined by this entry. The table will not be executed if 0 is entered. Entries less than 32 seconds will be rounded to a valid interval if they are within 1/512 (0.00195) second of a valid interval, otherwise error E41 will be displayed. Entries greater than 32 seconds are rounded to the nearest second.

The sample rate for a CR10 measurement is the rate at which the measurement instruction can be executed (i.e., the measurement made, scaled with the instruction's multiplier and offset, and the result placed in Input Storage). Additional processing requires extra time. The throughput rate is the rate at which a measurement can be made and the resulting value stored in Final Storage. The maximum throughput rate for fast single-ended measurements with standard software is 192 measurements per second (12 measurements repeated 16 times per second).

If the specified execution interval for a table is less than the time required to process that table, the CR10 finishes processing the table and waits for the next occurrence of the execution interval before again initiating the table (i.e., when the execution interval has elapsed and the table is still executing, that execution is skipped). Since no advantage is gained in the rate of execution with this situation, it should be avoided by specifying an execution interval adequate for the table processing time.

NOTE: Whenever the processing time of the user's program exceeds a table's execution interval, an error is logged in memory. The number of overrun errors can be displayed and reset in the *B mode (Section 1.6) or using the Telecommunications A command (Section 5.1). An overrun will also cause decimal points to appear on both sides of the sixth digit of the CR10KD. The decimal points will not appear around the G in LOG if the *0 Mode is entered before the overrun occurs.

In some cases, the processing time may exceed the execution interval only when the Output Flag is set and extra time is consumed by final Output Processing. This may be acceptable. For example, suppose it is desired to sample some phenomena every 0.125 seconds and output processed data every 10 minutes. The processing time of the table which does this is less than 0.125 seconds except when output occurs (every 10 minutes). With final output the processing time is 1 second. With the execution interval set at 0.125 seconds, and a one second lag between samples once every 10 minutes, 8 measurements out of 4800 (.17%) are missed: an acceptable statistical error for most populations.

1.1.2 SUBROUTINES

Table 3 is used to enter subroutines which may be called with Program Control Instructions in Tables 1 and 2 or other subroutines. The group of instructions which form a subroutine starts with Instruction 85, Label Subroutine, and ends with Instruction 95, End (Section 12).

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