Operator`s manual

SECTION 3. INSTRUCTION SET BASICS
3-6
nested 2 deep while the OR construction is
nested 3 deep. Branching and loop nesting
starts at zero within each subroutine and then
returns to the previous level after returning from
the subroutine.
Subroutine calls do not count as nesting with
the above instructions. They have a separate
nesting limit of seven (Instruction 85, Section
12).
Any number of groups of nested instructions
may be used in any of the three Programming
Tables. The number of groups is only restricted
by the program memory available.
3.9 INSTRUCTION MEMORY AND
EXECUTION TIME
The standard 21X has 978 bytes of program
memory available for the programs entered in
the *1, *2, and *3 program tables. Each
instruction also makes use of varying numbers of
Input, Intermediate, and Final Storage locations.
The following tables list the memory used by
each instruction and the approximate time
required to execute the instruction.
TABLE 3.9-1. Input/Output Instruction Memory
R = No. of Reps.
D = Delay
INSTRUCTION MEMORY EXECUTION TIME (ms)
INPUT PROG. MEASUREMENT RANGE
LOC. BYTES 1-4 or NA 5.* 11-14
1 VOLT (SE) R 15 38.0 + 19.2R 8.4 + 3.7R 5.5 + 2.4R
2 VOLT (DIFF) R 15 36.9 + 38.0R 7.8 + 6.9R 5.5 + 3.7R
3 PULSE R 15 0.2 + 1.2R
4 EX-DEL-SE R 20 38.0 + (19.2 + D)R 8.1 + (4.4 + D)R 5.3 + (2.8 + D)R
5 AC HALF BR R 18 38.8 + 40R 10.7 + 7.5R 7.5 + 5.1R
6 FULL BR R 18 41.8 + 73.0R 10.5 + 13.1R 7.6 + 7.4R
7 3W HALF BR R 18 41.2 + 76.8R 10.6 + 16.2R 7.1 + 11.0R
8 EX-DEL-DIFF R 20 38.1 + (19.2 + D)2R 8.1 + (4.2 + D)2R 5.3 + (2.8 + D)2R
9 FULL BR-MEX R 19 76.7 + 149.6R 15.7 + 28.2R 9.9 + 16.7R
10 BATT. VOLT 1 4 7.6
11 TEMP (107) R 15 5.0 + 8.4R
12 RH (207) R 17 7.9 + 7.0R
13 TEMP-TC SE R 18 40.8 + 23.2R 7.9 + 6.7R
14 TEMP-TC DIF R 18 39.2 + 42.7R 7.8 + 8.5R
16 TEMP-RTD R 15 0.4 + 2.7R
17 TEMP-INTERNL 1 4 14.0
18 TIME 1 7 1.4
19 SIGNATURE 1 4 1200
20 PORT SET 1 4 0.3
21 ANALOG OUT 1 5 10.5
22 EXCIT-DEL 1 11 1.0 + D
23 BURST MODE R
26 TIMER 1 or 0 4 0.54 to reset, 0.25 to load into location
101 SDM-INT8 25
102 SDM-SW8 16
103 SDM-AO4 0 6
104 SDM-CD16 6
* Range 5 uses a 1.67ms integration time; the other "slow integration" ranges (1-4) use 16.67ms
integrations. Range 15 uses a 25µs integration (ranges 11 - 14 use 250µs). The execution times for
instructions using range 15 are faster than those given for ranges 11 - 14 by approximately 225µs per rep
for single-ended measurements, and 450µs per rep for differential.