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Status Byte

The counter sends its status byte to the controller on a serial
poll. The bits in the status byte reflects different events or con-
ditions in the counter. There are two types of status bits:

A Conditional Bit indicates the current condition of what
its monitoring, all the time.

An Event Bit indicate that an event has occurred. When
the event occurs, the bit is set to 1. It is not reset to 0 until
a new measurement starts.

The different bits indicate the following information:

Bit

Function

Always 0

1 = SRQ has been sent

otherwise 0 (Event bit).

Abnormal bit. Always 0
during normal
measurements

1 if something is wrong.
Affects bit 0-3

0 = Main Gate closed

1 = Main Gate open

3-0

Depends on Abnormal
bit

see below (Event bits.)

Bit

Abnormal bit = 1

Abnormal bit = 0

Not Used

Measuring stop enable.

Time-Out

Measuring start enable.

Hardware fault

Ready for triggering

Programing error

Measuring result ready.

Only if SRQ-mask is set for Service-Request.

This is a conditional bit that monitors the Main-Gate
in the counter. When TOT MAN is selected the bit
will always be 0.

Measuring Start Enable indicates that the counter logic
is ready to start a measurement.

Measuring Stop Enable indicates that the counter logic ir
ready to stop a measurement.

These bits can be used to detect if the input signal to the
counter is present; If the counter never stops it’s measure-
ment and the status byte stops at:

XX00X1XX

No input signal. The measurement is
ready to start (bit 2 = 1) but the Main
Gate has not opened (bit 4 = 0).

XX011XXX

Input signal lost during measurement. The
measurement is ready to stop (bit 3 = 1)
but the main gate is still open (bit 4 = 1)

(X = don’t care)

NOTE:

SRQ is normally not used for these bits.

Ready For Triggering indicates that all preparations for a
measurement is completed. The preparation time depends
on selected functions. It can be up to 700 ms (when auto
triggering is selected).

If triggered mode is selected, the counter waits to be trig-
gered, otherwise it proceeds with the measurement. You
can have the SRQ-mask set for SRQ at ready for trigger-
ing. This way the controller knows when it is possible to
trigger the counter.

Measuring Result Ready indicates that the measurement
and calculation of the result is completed and that the re-
sult is present in the output buffer. If SRQ for is selected
for this event, or Free-run is OFF, the counting will stop un-
til the controller has read the result.

Programming Error is generated if the counter receives
messages with illegal syntax or values out of its range.

If ‘Programming error’ is generated, the counter will stop
measuring. It will continue to receive and store correct pro-
gramming messages and use them when the error status
is reset and a new measurement starts.

Correct the program before resetting the status message.

Use one of the following bus commands to reset the status
byte:

Go to local (GTL), Device clear (DCL) or selective device
clear (SDC).

Any of the following messages will have the same effect
on the counter:

D, FNC?, MEAC?, INPA?, INPB?, ID? or BUS?.

A serial poll will also reset the status message if the SRQ
mask is set for ‘SRQ at Programming error’.

Hardware Fault is generated when the counter displays
the codes described in ‘Error codes’ in the ‘Operating in-
structions’ in this manual.

Time-Out is generated when the set time-out period has
elepsed.

Possible Status Messages

Normal Measurement

The status byte changes as follows during a normal meas-
urement:

0, 2, 6, 22, 30, 14, 15, 0, .........