Table of Contents
Advertisement
7. If a buffer is not enabled (QO or any function
but FO),
only one reading will be sent in G3-G7.
8. If accessing the reading buffer in the G7 mode, the byte
count will show the number
of readings left in the
reading buffer.
ASCII Data Format
When the instrument
is placed in the GO through
G5
modes, the data string is made up of ASCII characters with
the general fromat shown in Figure 4-6. The various sec-
tions of the data string include:
1. Prefix (GO, GZ, G3, and G5): Indicates
the type of
measurement
function
in effect (for example, TRMS).
The prefix is omitted in the Gl and G4 modes.
Z.Mantissa:
A 4% digit (+32,767 counts) signed value
representing
the instrument
reading. Note that usable
resolution
is only 2% digits (f128 counts) for sampling
rates above lOOkHz, or for more than 32,768 samples.
3. Exponent:
Indicates a multiplier
for the mantissa.
4. Suffix: Indicates the channel number and the remain-
ing number of reading buffer locations remaining when
the correct format mode is in effect. When
in the
waveform mode, the buffer location suffix indicates the
individual
sample number, O-65,535. The buffer suffix
will be omitted if the reading buffer is disabled (QO) and
if the unit is not in the waveform mode.
NOTE
NOTE
When requesting waveform measurements
in G6
When requesting waveform measurements
in G6
or G7 data formats, raw binary data in offset binaq
or G7 data formats, raw binary data in offset binaq
will be sent. In any other function the data format
will be sent. In any other function the data format
will be in 16 bit twds-complement
form.
will be in 16 bit twds-complement
form.
Binary Data Format
When the instrument
is operated in the Gh and G7 mwies,
it will transmit data in raw binary form with the general
format shown in Figure 4-7. The main advantage to using
the binary data format is that fewer bytes are inwIved,
so
data transmission
is more rapid than when using the
ASCII data format. Note that no terminator
is sent in the
G7 mode, and that the byte count excludes the four bytes
in the status word.
The two binary modes include a 4.byte status word '1s
shown in Figure 4-7(c). These bytes indicate the folkwing:
Byte 1: Overflow,
zero, ~Ihi8-bit mode, invalid
numeric
value, waveform present in measurement
buffer.
Byte 2: Range and channel
Byte 3: Function
Byte 4: Exponent
in 2s complement
form
N=NDRMAL
_J
+J
kdSA
'i'
DEFAULT
D=D"ERFLOW
:
CHANNEL
TERMINATOR=CR
LF
NUMBER
Z=ZERDED
READING
EXPONENT
I=IN"ALID
MEASVREMENT
1
RMS=TRMS
NOTE: SUFFER LOCATION SHOWS
A"G=A"ERAGE
SAMPLE nnnnn IN WAVE
+PK=+PEAK
FORM MODE
-PK=-PEAK
D,F=CH,~CH2
RAT=CHI,CH2
DE"=STANDARD
DEVIATION
P-P=PEAK-TO-PEAK
,NT=INTEGRAL
OCV=WAVEFORM
RCL=RECALL
MODE
Figure 4-6. ASCII Data Format (GO to G5)
4-27
Advertisement
Table of Contents
