Campbell Scientific CR10 CR10 Measurement and Control - Page 135

lf SPLIT is not available for converting

the

raw

A/D, the

following

A/D

format

information

is

provided for

decoding purposes.

At

the

start

of

the

series

of

measurements,

the

CR10 makes

a

self-calibration measurement. The

calibration

data

is

sent at the

staft

of

the

measurement

data.

The

serial

data

is sent as a series

of

signed

2

byte integers (most significant byte

sent

first;

i.e., Integer

=

256

*

byte

1

+

byte

2):

l't...1n.

The

first integer, l1

is

a

start of

output

identifier,

FCxx

(hex), where the

first

byte

is

always

FC (never

seen

in

the data), and

the

second byte is

a

number less

than

100

(decimal,

64

hex),

which

is

the

Instruction

Location Number

of

Instruction

23

in

the

program

table.

12

divided by

13

is

the

multiplier

and

14

the offset

(to

the

raw data) determined by

the first

calibration.

12

is a

fixed value

determined by

the input

range

selected.

15

through ln

are

the

raw measurement data.

Thus, the value of the

first

measurement sent

(M1)

in

millivolts

is:

Mr

=

ly'ls

(ls

-

l+)

The measurement data

are

sent in

the order

that

the

measurements

are

made (i.e., the

first

measurement for each channel, then

the

second

measurement

for

each channel, etc.).

NOTE:

When

the

raw

serialdata

option

is

selected, the calibration values are

for

conversion

to

millivolts

only.

Parameters

11

and

12

are

ignored.

SCAN

INTERVAL

lnstruction

23

has its own scan interval

independent of the

execution

interval of the

program

table

in

which

it

resides.

The

resolution

of

the clock timing the execution

intervalis

813 nanoseconds.

This

scan

interval,

entered in

Parameter

5

(in milliseconds),

is

the

time

between

each

scan of the specified

channels

(i.e., if

4

channels

are specified

in

Parameter

1,

and

the scan

interual is

5

ms, then

the

4

measurements

willbe

repeated every

5

ms).

The

minimum time

that

is

allowed

per

measurement is

1.333

ms.

The

maximum

time

that

is

allowed

per

measurement

is

50

ms.

lf

the scan interval entered does not allow this

much

time per

measurement (e.9.,

if

with

4

reps,

an

interval less

than

5.332 ms

is

entered),

an error

code,

E

61,

will

be displayed when

the

program

is

compiled.

When

sending data to

the

serial port,

the

rate at which the data

can

be

SECTION

9.

INPUT/OUTPUT

INSTRUCTIONS

transferred

may limit

the scan

interval (e.9., at

9600 baud

the

minimum

time

per

measurement

is

2.2

ms).

BursUTelecommunications Considerations

lf

a Burst

measurement

sequence

is

in

progress,

raising the

datalogge/s

ring line will

abort

the

Burst

sequence.

Peripherals which

raise

the

ring line

are

modems

(i.e.,

RF,

Telephone, Short Haul, MDg, SC32A) or

the

CRlOKD.

lf

the

Burst

Measurement

Instruction

is

encountered while

telecommunications

is

in

progress, the destination

of

the

data determines

whether or

not

the

instruction is executed:

Burst

data

sent

to input locations

lf a CR10 already

in

Telecommunications

mode

executes a Burst instruction specifying

that

Burst

data

be

sent

to

input locations, all

telecommu nication activity

will

be suspended.

After

the

Burst

trigger condition

is met and

all

Burst measurements

made,

telecommunications

activity

c?Il

IOSUtrlg;

Burst

data

sent

to

Serial

UO

Port

lf

the

Burst instruction specifies that Burst data

be sent to the serial port (i.e., Storage Module),

CR10 program execution

willpause untilthe

Telecommunication

mode

is

exited.

During

this

pause

telecommunications

(i.e.,

view

input

locations, Monitor Mode with Term, etc.) can

continue.

No Burst measurements

are

made

while

in

telecommunications and

no Burst

data

is

sent to

the

serial

port.

After telecommunications

has ended,

datalogger

program execution will

resume

as

if

the Burst

instruction were

just

executed.

NOTE:

Instruction

23

can be aborted by

pressing

any

key on the

CR1OKD

Keyboard

Display.

2

2

02:

03:

PARAM.

DATA

NUMBER

TYPE

01:

2

DESCRIPTION

Repetitions (no. of

channels)

Range

code

(13-15)

Single-ended

or

differential channel

for

first

analog

measurements

9-11

Campbell Scientific CR10 CR10 Measurement and Control - Page 135

BursUTelecommunications Considerations

Page 135 highlights