DL716 DIGITAL SCOPE
NIIMI Yoshihisa*1 TAKESHITA Yukihito*1 YAMAMOTO Chiaki*
The newly developed digital scope DL716 features 16 channels and a
maximum sampling rate of 10 MS/s. The DL716, which succeeds the DL708 (8
channels), further strengthens the DL700 Series. The electronic recording function
has been enhanced to allow for the recording of 256 M Word to hard disk drive and
fast replay of data. The Replay function allows swift detection of errors in
recordings over a long time span and improvements in hardware and software have
increased PC compatibility. We standardized all communications ports (SCSI/RS232/GP-IB) and created PC software with DL main unit features like the Replay
History function. This product supports waveform data from PCs in various formats
including BMP, and CSV for spreadsheets. The amount of supported analog
modules has been increased to seven and the addition of operation menus for all
channels has increased flexibility.
INTRODUCTION
here has been increasing demand, not only in the
mechatronics field but also in the multimedia field, for a
T
measuring instrument that can observe fast and slow waveforms
as well as waveforms that require various signal conditioning
(thermocouples or strains). Users from these fields who tend to
use oscilloscopes, want in digital scopes the same operability as
oscilloscopes. In response to these demands, in 1997 we
introduced the DL708, an 8-channel digital scope, and have since
developed the DL716, a 16-channel version, to enrich the lineup.
Both of them were developed under the same basic concept of
enhancing electronic recording. With the DL716, we redesigned
the configuration, ASICs, and software, which allowed us to
intensify the advanced acquisition functions through the addition
of ultra-large memory and strengthening of PC compatibility. As
for the display, the DL716 inherits the 10.4-inch color TFT LCD
from previous models. Figure 1 shows an external view of the
DL716.
Data Acqusition
(1) Recording to Large Memory and Hard Disk Drive
The most distinguished feature is its ultra-large memory,
which has a maximum capacity of 64 M words (for
simultaneous recording on 4 channels). A maximum of 256
M words (for 1 channel recording) can be collected and
recorded to the hard disk drive. Users can observe waveforms
recorded to memory for 6.4 seconds at a rate of 10 MS/s, and
to the hard disk drive for a maximum of 42.6 minutes at a rate
of 100 kS/s. The use of memory with the DL716 enables
1
FEATURES
The DL716 offers the following advantages:
*1 Test & Measurement Business Div.
DL716 Digital Scope 9
Figure 1 DL716 Digital Scope
measurement four times longer than that of the DL708 and its
acquisition capabilities are unparalleled for this type of
waveform measuring instrument.
(2) Replay
Since all of the acquired 256-M word data cannot be displayed
on a single screen due to the display resolution, the DL716
incorporates the replay mode. This function displays a
maximum of 1-M word (min. 1-k word) of waveform data on
the screen, and the scrolling mode allows the user to smoothly
replay the data after acquisition has ended as shown in Figure 2.
The replay function allows users to detect problems quickly and
the scrolling speed can be finely adjusted.
(3) All Channel View Menuue
The DL716 is equipped with the All Channel View Menu
shown in Figure 3. Users can set channels while confirming
the settings of all channels on the screen. On the other hand,
the DL716 continues to offer the operability of oscilloscopes,
as users can set each channel while viewing waveforms. The
DL716 allows users to select the mode of display they prefer.
Also, this product has a Copy to Same Module function,
which enables the copying of settings from one channel to
other plug-in modules of the same type and thus eliminates
the complexity of multi-channel setting.
(4) Time Trigger
The time trigger is activated automatically at a specified
measurement start time and at specified intervals (in hours
and minutes) thereafter. This is useful when continuously
operated equipment needs to be monitored at a specified time.
In combination with the History Memory function, it allows
for the storing of up to 1000 waveform screens at specified
intervals.
Figure 3 Simultaneous Channel Display
Plug-in Modules
(1) High-speed and High-resolution Modules (10 MS/s
sampling, 12-bit resolution, and 850 V input)
To meet the increased demand for speed and resolution, we
upgraded the resolution of high-speed modules (10 MS/s)
from 10 to 12 bits. The DL700 series supports seven plug-in
modules, including the high-speed isolation module, highresolution module, temperature module, logic input module,
and strain module.
256 M words
Replay screen
Replay
Scroll direction
setting
Fine adjustment of
scroll speed
1 M words
Scroll
Direction
<<
>>
>
Scroll Speed
<
Lo Hi
][
Figure 2 Replay Function
10 Yokogawa Technical Report English Edition, No. 30 (2000)
Internal
hard disk
drive
SCSI
Figure 4 Replay Function
PC Compatibility
(1) SCSI Interface (3.2-GB internal hard disk drive)
The DL716 comes standard with a SCSI interface, to improve
PC compatibility. By allowing the internal hard disk drive to
be directly connected to a personal computer, users running
Windows 95/98
*2
can read data on the internal hard disk drive
using application software (see Figure 4). To be more precise,
they can display waveforms directly on a
personal computer or read the data using
spreadsheet software without having to
worry about transferring data after it has
been captured. Data transfer is so fast that
users are unaware that the process is taking
place.
Data that can be read on a PC includes
1) bitmap image files of waveforms (BMP
or TIFF, color or black-and-white),
2) measured raw data, and 3) automatically
measured text data. Figure 5 shows an
example of using bitmap image files on a
personal computer. Waveform images that
had to be printed out with conventional
models can now be stored on a hard disk as
bitmap data to be used on a personal
computer later as necessary.
The DL716 also comes standard with a
variety of other interfaces essential to
interoperability with a personal computer
(floppy disk drive, GP-IB, RS-232, VGA,
GO-NOGO, and Centronics)
(2) Waveform Viewer on PC (Waveform Viewer for DL series)
We have provided software for displaying data of the DL
series. An important feature of this software is that it allows for
256-M word waveform data to be processed on a personal
computer. As personal computers are not equipped with
compressor hardware, the DL716 transfers captured waveform
Figure 5 Use of Waveform Images Stored on Internal Hard Disk Drive
DL716 Digital Scope 11
Replay View on PC
History View on PC
Figure 6 Replay and History Memory Functions on PC
data compressed in two steps to the personal computer to
enable fast data display (see chapter 3). Waveform Viewer
provides the Replay and History Memory functions of the
DL716 on the personal computer (see Figure 6). Waveform
Viewer also converts data to a format supported by spreadsheet
software (CSV).
SYSTEM CONFIGURATION
Hardware
Figure 7 shows a block diagram of the DL716. The DL716 is
basically the same as the DL708, but incorporates additional
features such as ultra-large memory, 16-channel measurement,
and two ASICs for support of the Replay function.
The ADP (Acquisition Data Processor with 80,000 logic
gates) simultaneously processes input data from four channels;
that is, it compresses data, performs computations, and detects
trigger levels. Five ADPs are used in the DL716, four for 16channel measurement and one for an extended logic circuit.
The ACL (Acquisition Control Logic with 50,000 logic
gates) mainly controls acquisition sequences and addressing of
waveforms stored to memory. The DL716 incorporates 64 units
of high-speed commercial DRAM as waveform memory. Its
operating voltage is 3.3 V and capacity is 64 M bits (512 MB in
total). DRAM needs periodical refreshing. The five stacks of
FIFO (First-in First-out) provided for each channel and the
writing speed of memory (12.5 MHz), 25% faster than the
acquisition speed (10 MHz), makes it possible to maintain
refreshing time.
Moreover, ADP’s compression process works with DMA
(Direct Memory Access) to make the system configuration
simple.
Principles of Replay Function
The replay must have the capability to scroll 256-M word
data as smoothly as possible. This is nearly impossible using
conventional methods because of the long compression time
required for data. To overcome this problem, the hardware and
software of the DL716 work together to compress captured
waveform data in two steps (1/100 and 1/1000) (see Figure 8),
and then the compressed data is stored along with the raw data to
memory or the internal hard disk drive. When replaying the data,
it reads the compressed data according to the zoom ratio. Quick
scrolling allows for up to 1000x display of data.
Compressing the data not only contributes to increased replay
speeds on the DL716, but also on the personal computer.
12 Yokogawa Technical Report English Edition, No. 30 (2000)
Module Block Diagram
Plug-in module CH1 to Ch16
High-speed Isolation module
High-speed module
High-resolution, module
H
L
Temperature module
RJC
+
-
OFFSET
AMP
+
ATT
Isolation Block
ATT
OFFSET
ATT
H
AMP
L
High-speed Logic Probe
Isolated Logic Probe
DIFA
+
-
Floating Common
Bridge Excitation
OFFSET
AMP
+
+
AMP
FLT
Isolation Block
AMP
Isolator
FLT
Isolation Block
FLT
AD
FLT
AD
AD
AD
1chip
CPU
Logic Input module
POD-A
8
POD-B
Strain module
FLT
AD
Acquisition Block Diagram
12
Acquisition
Data Processing
(ADP)
12
16
CH1 to CH8
Acquisition
Data Processing
(ADP)
CH9 to CH16
Acquisition
Data Processing
(ADP)
(Logic1, Logic2)
16
8
16
Optional memory
(Max. 16MW/CH)
Acquisition
Memory
(200kW/CH)
Acquisition Control
ADD
(ACL)
Logic
ADD
Optional memory
(Max. 16MW/CH)
Acquisition
Memory
(200kW/CH)
Acquisition
Memory
Extended Logic
Input
Ext clk in
Ext trig in/out
FDD
CPU Block Diagram
CPU
Main Memory
HDD
GP-IB
Serial
Port
Centro
Port
Port
10.4 Color
TFT Display
Display ASIC
Display
RAM
SCSI
GP-IB
RS-232
Centro
Built-in
printer
SCSI
Port
Figure 7 Block Diagram of the DL716
APPLICATIONS
This chapter gives examples of applications where the DL716
is suitable.
MD Player
MD (Mini Disk) players incorporate various mechanical and
electrical components, and thus there are a wide variety of signals
to be measured, such as servomechanism, sound, and digital data
signals (see Figure 9). With the DL716, different servo signals or
sound signals that require isolated measurement (more than 10
Data Compressed to 1/1000
HDD
AD
Data Compressed to 1/100
ADP
Memory
isolated analog channels), can be measured together with digital
signals surrounding the micro computer (approximately 40 bits).
MD players are characterized by high-speed pre-read control
to avoid skipping data and save power consumption. As shown in
Figure 10, it pre-reads 40 seconds worth of sound data in a few
seconds (read data is stored to DRAM for replay at normal
speed). During the remaining time it turns off unneeded control
circuits to save the battery (power consumption). Since all the
Threaded
motor
PWM
MD
Spindle
motor
Servo driver
PWMPWM
Focus
tracking
actuator
Pick up
RF AMP
Servo Sound
MD player LSI
DRAM for
vibration-resistance
Micro
computer
Raw Data
Digital data of 40 bits
Figure 8 Data Compression in Replay Mode
10 channels for isolated analog
Figure 9 Application Example of MD Player
DL716 Digital Scope 13
First several seconds
40 seconds
Measurement Data storing
Use of data
Reading
Normal
operation
WR
Sound reproduction
RD
DRAM for vibration-resistance
Power saving time
Figure 10 MD’s Vibration-resistant/Power-saving Mode
phenomena must be recorded over these 40 seconds, the DL716 is
very effective because of its ultra-large memory. It can record 80
seconds of data through simultaneous sampling of 16 channels at
a high-speed of 200 kS/s, and then store as much as 512 MB of the
recorded data to the internal hard disk drive.
Sharing of Internal Hard Disk through Network
The internal hard disk of the DL716 can be shared with other
personal computers through a network using the network file
sharing functions of Windows 95/98
*2
as shown in Figure 11.
This enables users to share digital data (huge amounts of raw data
or bitmap images of waveforms), captured in the field and stored
to the internal hard disk drive, with personal computers in remote
offices. Therefore, this new approach to measurement completely
eliminates the need for recording data on paper in all stages, from
the collection of data to its utilization.
SCSI
Internal
hard disk
Windows 95
PC in the
field
Network
Figure 11 Sharing of Internal Hard Disk through Network
CONCLUSION
As aforementioned, the DL716 allows multi-channel
measurement and has enhanced digital recording capability. We
believe that the DL716, as well as the DL708, will be very
advantageous in a wide variety of measurement applications,
from temperature to high frequency (MHz) signal measurement.
We will further expand this series in line with changes in the field.
REFERENCES
(1) Kato S., Ito S., Takeshita Y., Mizusawa T., et al., “Digital
Scope DL708E”, Yokogawa Technical Report, No. 26, pp.
27-30 (1998).
(2) Nagata.Y, “Power-saving Technology for MD Player”,
Electronic Engineering, Vol. 40, No. 4 pp. 30-34 (1998).
*2 Windows 95/98/NT are registered trademarks of Microsoft
Corporation.
14 Yokogawa Technical Report English Edition, No. 30 (2000)
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