ScannerMAX Mach-DSP User manual

Mach-DSP User’s Manual
Document Number: MACH-DSP-9021 Page 1
.ScannerMAX.com
Mach-DSP Servo Driver
and associated software
Users Manual
October 2020

Mach-DSP User’s Manual
Document Number: MACH-DSP-9021 Page 2
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Table of Contents
1.0 Introduction
2.0 S ecifications, Dimensions and Mounting
3.0 Connector locations and functions
3.1 Power Supply
3.2 Analog and Digital Command input, and XY2-100 Inter ace Daughterboard
3.3 Status and control signals
3.4 Control Panel Serial inter ace
3.5 Test and Thermistor inter ace
3.6 Scanner inter ace
4.0 Fault monitoring, rotection circuitry and indicator lights
4.1 Fault Detection
4.2 Fuses
4.3 Light Color and Meaning
5.0 Servo Overview
5.1 Servo Class, terminology, and con igurations
5.2 Servo con igurations possible with the Mach-DSP
5.3 Servo architecture and digitizing resolution
5.4 Dual Output Filters (low-pass, notch, or phase-lead)
6.0 Command In ut waveforms and im lications
6.1 Large-Signal and Small-Signal wave orms
6.2 Step wave orms
6.3 Raster wave orms
6.4 Vector wave orms
7.0 Mach-DSP Servo Control A lication rogram
7.1 Setting up communications
7.2 Menus, toolbar, status area, and control parameters
7.3 Basic servo parameters
7.4 Intermediate servo parameters
7.5 Advanced servo parameters
7.6 Control-related (TTL Input and Output) parameters
7.7 Pangolin-only servo parameters
7.8 Saving and recalling scanner tunings rom memory and iles
8.0 Built-in Tools accessed using the Mach-DSP rogram
8.1 Test Signal generator
8.2 Oscilloscope and Analog Test Point (user-de ined) Outputs
8.3 Dynamic Signal Analyzer
8.4 Error Modi ier (nonlinear correction)
9.0 Servo Tuning Instructions
9.1 Equipment needed
9.2 Initial “PD” Tuning
9.3 Setting Position O set and Position Scale
9.4 Going beyond PD – adding integration to accomplish PID tuning
9.5 Care ul tuning leads to optimal per ormance
9.6 PDF con iguration and tuning
10.0 RoHS, REACH and CE Com liance Statements
11.0 More Information, including Patents and Trademarks

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1.0 Introduction
Pangolin has been using the ord “Mach” (pronounced mock) as a model designation
for our industrial-grade servo drivers since 1998. Back then, e introduced a unique
servo amplifier having four separate coil drivers for a custom industrial galvanometer,
and dubbed the project “Mach 4”.
Completely setting aside the fact that the ord Mach is a cool ord – one hich
conjures images of the fastest fighter jet airplanes, the ord is actually entirely
applicable to the field of galvanometer scanning. Indeed, ScannerMAX scanners utilize
unusual materials and techniques in their rotor construction, and hile choosing these
materials e often consider the speed of sound through these materials (i.e. the Mach
number). For this reason, e continue to use the ord Mach for our servo drivers.
The Mach-DSP servo driver is Pangolin’s latest and most advanced development in
servo control technology. By taking advantage of high-speed floating-point digital signal
processors, 16-bit data converters, direct digital command input, and highly-
configurable servo algorithms, the Mach-DSP provides full-function, t o-axis servo
driver electronics in a cost-effective and compact package. Many advanced techniques
and user-customizable features are embodied ithin the Mach-DSP hard are and
soft are hich, hen combined ith Pangolin’s ScannerMAX scanners, provide a level
of speed, accuracy and convenience that ere unattainable before no .
The Mach-DSP can be accessed and configured using a PC-based Graphical User
Interface soft are package, here the built-in Test Signal Generator, Oscilloscope and
Dynamic Signal Analyzer can be used to monitor and adjust the more than 50
performance parameters per axis. These performance parameters can be stored in four
separate memory areas (called “tunings”) for instant access and recall at any time.
Additional features and behavioral customizations can be added via firm are updates
that take only a fe minutes to do nload using the PC-based soft are, helping to make
the Mach-DSP a “future-proof” product. Moreover, since the current version of Mach-
DSP firm are uses only a fraction of the on-board memory and only around half of the
CPU band idth, it is possible that customized applications may also be loaded into the
Mach-DSP, helping to reduce the size, po er consumption and cost of an overall laser
system. (Contact us about ho customization could be done for your application.)
The Mach-DSP servo driver as created ith OEMs in mind, incorporating a simple yet
comprehensive and flexible interface structure. This, together ith the modest po er
requirement and compact size allo s laser system manufactures to package the servo
driver electronics, the scanners, and often the po er supply as ell, directly into the
laser projector head.
The purpose of this manual is to familiarize you ith the functionality of the Mach-DSP
servo driver. This manual also provides a brief introduction to the process of servo
tuning, although hen buying a complete system (scanners, mirrors, mount, servo
driver, and cables) the Mach-DSP should arrive already tuned at the Pangolin factory.
We also offer tutorial videos on our ebsite that provide more in-depth information.

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2.0 S ecifications, Dimensions and Mounting
Analog and Digital Command In ut
♦ Analog Differential Voltage Range ±10 volts differential for full scale
(other voltage ranges are also possible)
♦
Analog Input Impedance 20KΩ differential
♦ FB4 and XY2-100 digital serial 3.3V direct-connect or RS-422 differential
Position Test Point Out ut ±10 volts; scanner-dependent scale
Current Test Point Out ut ±10 volts; full scale (1 volt per amp)
AGC Test Point Out ut 0 to –15 volts, full scale
User-assignable Analog Out uts six outputs; ±5 volts; user-adjustable scale
Digitizing resolution 16-bits for all analog inputs and outputs
Enhanced resolution up to 18-bits for Command; 17-bits Position
In ut Power
♦ Voltage ±12V to ±30 Volts DC (version dependant)
(Standard version requires ±24V. See Po er Supply section for information.)
♦ Quiescent Current +200mA, -230mA
(servo enabled, galvos at rest)
Motor Drive Power
♦ Dynamic Current (per axis) up to 5 Amps RMS; 10 Amps Peak
(scanner and po er supply dependant)
Control I/O
♦ Programmable on-off “TTL” Inputs t o separate optically-isolated inputs
♦ Programmable on-off “TTL” Outputs t o separate optically-isolated outputs
♦ Bi-directional USB/Serial Ports t o accessible 3.3V-compatible ports
Fault Monitoring and Protection
♦ Fast-blo fuse protection X- and Y-axis motor outputs
♦ Fault monitoring shutoff / soft-start Over-position, Over current, Over temp.,
Po er supply under- and over-voltage,
Scanner AGC fault or cable unplugged
O erating Tem erature Range 0°C to 60°C
Size W x L x H
2.95” x 3.94” x1.3”
(75mm x 100mm x 33mm)
Mass 170 grams

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Mach-DSP Package Dimensions
(millimeters)

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2.1 Mounting the Mach-DSP servo driver
To transmit heat that is generated during operation, the Mach-DSP servo driver should
be mounted to the chassis of a projector or other enclosure. T o semi-circular cutouts
are provided on the rear surface of the Mach-DSP servo driver for mounting purposes.
Since the rear surface of the Mach-DSP may not be completely flat, and the projector
housing may also not be flat, Pangolin provides thermal interface material consisting of
heat sink compound filled ith aluminum nitride or silver. That heat sink compound
should be spread onto the rear surface of the Mach-DSP servo driver before being
mounted onto the projector chassis.
Note that all heat sink compounds include oil as a retaining element, and this oil may
evaporate over time. Therefore if the Mach-DSP ill be used inside the same projector
housing along ith sensitive optics, it may be desirable to use a different thermal
interface material, such as Sil-Pad made by Bergquist.
Once the Mach-DSP is operational, you should atch the “Servo board temperature” as
reported by the Mach-DSP PC application program. Ideally, the Mach-DSP board
should be operated at temperatures of 50C or less. Ho ever, the Mach-DSP ill
continue to operate at temperatures ell above that. Nevertheless, if the temperature
reported exceeds 50C on a regular basis, it might be ise to revisit the thermal interface
material bet een the Mach-DSP and the projector housing, or increase the surface
area, to hich the Mach-DSP is mounted, to improve heat dissipation.

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3.0 Connector locations and functions
Please refer to the diagram belo for an overall vie of the location and function of
each connector. Note that each connector on the Mach-DSP is unique, thus helping to
prevent signals from becoming accidentally mismatched or misconnected.

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3.1 Power Supply
Po er is supplied to the Mach-DSP through a connector that is located approximately in
the middle of the board, to ard the rear (near the po er amplifier components). The
connector pin functions are sho n in Table 3.1.
The standard version of the Mach-DSP can be operated ith po er supplies ranging
from ±18V to ±30V. Ho ever, ±24V is required for optimal large-signal performance.
Operating the standard version ith higher po er supply voltages ill not provide any
increase in scanning performance, but ill generate more heating of the servo driver.
Ho ever, operating the standard version at lo er po er supply voltages ill incur a
decrease in large-signal performance.
Note that the component values in the po er amplifier section are optimized to operate
at specific po er supply voltages you specify at the time of purchase. When these
components are matched to the po er supply used, this results in the best possible
large-signal performance. Upon request, the Mach-DSP can be special-ordered to
operate optimally ith po er supply voltages as lo as ±12V or as high as ±30V.
The actual po er supply current requirements are dependent on the application, and
ill vary as a function of the magnitude and duty cycle of galvo acceleration required.
Idle current is around 200mA from each of the supply rails, so this represents the
minimum current requirement. Laser marking and material processing applications
typically dra ell under 1 amp from each supply rail hile some raster imaging
applications and laser lightsho s may require several amps continuous.
The Mach-DSP servo is rated for a maximum +/-5A RMS and +/-10A peak output
currents, per axis.
Table 3.1: Power Connector
Pin Function
1 Positive supply
2 Negative supply
3 Ground
4 Ground
Mating Connector Housing: MOLEX Mini-Fit Jr: 0039012040
Mating Connector Pins: 0039000073 or 0039000074
S ecified Wire Size: AWG #18-#24
The Mach-DSP as designed ith some degree of protection on the po er supply pins.
Nevertheless, YOU MUST OBSERVE POWER SUPPLY POLARITY NOTED IN THE
TABLE ABOVE, AND OBSERVE THE MAXIMUM OPERATING VOLTAGE FOR
EACH MACH-DSP. APPLYING ELEVATED VOLTAGES, OR NEGATIVE VOLTAGE
TO PIN 1, AND/OR POSITIVE VOLTAGE TO PIN 2 MAY RESULT IN IRREPARABLE
DAMAGE TO THE MACH-DSP AND WILL VOID THE WARRANTY!!!

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3.2 Analog and Digital Command Input
Using the Mach-DSP PC application soft are (described in Section 7 of this manual),
each axis of the Mach-DSP may select either Analog Input or Digital Input as the source
of the Command signal. Analog Input is the most common, and is the default.
When the Input Source is set to Analog, then the Mach-DSP ill receive its Command
signal as a digitized version of the voltage appearing on the 6-pin Analog Command
Input connector. When the Input Source is set to Digital, then the Mach-DSP ill receive
its Command signal from through-hole pads (or an optional XY2-100 Interface
Daughterboard) located just to the right of the Status/Control connector.
3.2a Analog Command Input
The Analog Command Input connector is located on the left side of the board. The
connector pin functions are provided in Table 3.2a:
Table 3.2a: Analog Command In ut
Pin Function
1 + X-axis command input
2 Ground (see belo for details)
3 - X-axis command input
4 + Y-axis command input
5 Ground (see belo for details)
6 - Y-axis command input
Mating Connector Housing: MOLEX Micro-Fit Jr: 0430250600
Mating Connector Pins: 0430300001 through 0430300012
S ecified Wire Size: AWG #20-#30, depending on pin type
Analog Command In ut Descri tion
The analog command input to the Mach-DSP is a true differential input that accepts a
full-scale command of ±10V differential (i.e. ±5V for the + input and ±5V for the – input,
or ±10V for the + input and 0V for the – input). For noise sensitive applications, a true
differential signal should be provided through a t isted and shielded ire pair.
Im ortant Information about Use with a Single-Ended Signal Source
Some industrial clients and university clients use common off the shelf DAC boards
from National Instruments and the like, hich offer only a positive (+) signal output and
ground, and do not offer a negative (–) signal output. Clients commonly ask us ho to
make the connections bet een this kind of signal source and the Mach-DSP.

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It occurs often that clients mistakenly believe they should connect their “ground” from
the source to pins 2 and pin 5 of the Analog Input connector of the Mach-DSP. (After all,
pins 2 and 5 are labeled “ground” above…) While this ill sort of ork, it ill also very
likely cause inaccurate scanning as ell as cross-talk bet een X and Y axes. The
reason is not obvious, and is covered in the book LASER SCANNERS: Technologies
and Applications, by William R. Benner, Jr (designer of all ScannerMAX products
including the Mach-DSP servo driver). See the chapter that covers Making the Right
Connections or Per ect Laser Images.
Nevertheless, if you have a single-ended source, in most cases the best way to
connect it to the Mach-DSP is to connect the + output of the DAC board to pin 1 (the
+X-axis command input) and/or pin 4 (the +Y-axis command input), and connect the
“ground” from the signal source to both pin 3 (the -X-axis command input) and pin 6 (the
-Y-axis command input) on the Analog Command Input connector. Doing this ill take
maximum advantage of the differential receiver in the Mach-DSP, allo ing it to remove
any noise picked up bet een the signal source and the Mach-DSP, and more
importantly, allo ing it to subtract out any “ground bounce” and other phantom po er
supply ground currents.
In most cases, do not connect to ins 2 and 5 on the Analog In ut connector
It is very rare indeed that clients should make any connections to pins 2 and 5 of the
Analog Input connector. (Again, for all of the reasons hy, please read the book
mentioned above.) Pins 2 and 5 are connected to the other pins labeled “ground” on the
Mach-DSP, including the Scanner interface and Po er Supply connector. In most
cases, best performance ill be had using a single-point-grounding-scheme, ith that
single point being located at (or very close to) the po er supply.
Voltage level of the in ut signal, and corres onding scan angle
The “Input Scale” is fully adjustable using the Mach-DSP Servo Control soft are
application, and it is possible to accommodate input voltage levels ranging from ±1V to
±10V differential, and have that correspond to any scan angle up to the maximum
provided by the scanner connected (greater than 100 degrees optical peak-to-peak ith
ScannerMAX scanners).
Ho ever, to take full advantage of the dynamic range provided by the 16-bit Analog-to-
Digital converter front end of the Mach-DSP, the input signal should have a voltage level
of ±10V differential. (When using a single-ended source, this corresponds to a voltage
range of –10V to +10V at the + axis inputs, and 0V at the – axis inputs.) Of course the
Mach-DSP can be special ordered for other full-scale signal ranges. If you have any
questions or concerns about this, please contact us to discuss your requirements.
In ut voltage range and common-mode rejection
The inputs are true differential, and as long as each of the + and – inputs do not exceed
20V, the system ill provide high common-mode rejection.

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3.2b 3.3-volt L-level Digital Command Input with Status Feedback
The Digital Command Input and Status feedback signals (and a fe unrelated signals)
are provided on unpopulated 100-mil-spaced through-hole pads located directly to the
right of the Status / Control connector. Table 3.2b belo describes the signals:
Table 3.2b: Digital Command In ut
Pin Function
1 Ground (pin 1 indicated ith square pad)
2 (reserved “Po er Amp Enable active lo ”)
3 Serial Port Y-axis data input (Position Feedback output for FB4)
4 Serial Port X-axis data input (XY-axis data input for FB4)
5 Serial Port Frame Sync input
6 Serial Port Clock input
7 (reserved “PWM po er amp clock”)
8 (reserved “PWM po er amp clock”)
Signal descri tion
As implied by Table 3.2b above, Digital Command Input communication is presently
facilitated through a multi- ire serial interface consisting of Clock, Frame Sync, one or
t o axis inputs, and an optional Status feedback output. The XY2-100 protocol uses
separate inputs for X-axis data and Y-axis data. The FB4 protocol uses a single input
for both X and Y data, and uses a single output for Position Feedback.
Voltage Levels
The digital signals found on these unpopulated through-hole pads use 3.3V TTL signal
levels. These signals may be connected directly to other 3.3V microprocessor-based
equipment that is located physically close to the Mach-DSP. For equipment located
farther (such as typical equipment that uses the XY2-100 standard), an optional
daughterboard (described later in this manual) can be fitted to the Mach-DSP, hich
adapts RS-422 differential signals to the 3.3V signal levels.
Additional un o ulated through-hole ins nearby
In addition to the 8 unpopulated through-hole pads mentioned above, there may be
additional unpopulated pads nearby, such as 5 or 6 pads, depending on the date of
manufacture. Those are reserved for future use and you should not connect to them.
Available cables
Digikey part numbers 1528-1964-ND and 1528-1967-ND may be soldered to those
unpopulated pads, and thus used to connect your digital signals to the Mach-DSP.

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XY2-100-com atible rotocol
Refer to the diagram belo , hich illustrates the signals and phase relationships.
Looking at the diagram above, you ill note that signals that are sent to the Mach-DSP
must change on the lo -to-high transition of the clock; signals are observed by the
Mach-DSP on the high-to-lo transitions of the clock.
Reception of a ne Input Command begins hen the Frame Sync line is brought high,
follo ed by a high-to-lo transition of the Clock line. During this same high-to-lo clock
transition, the first bit of data is also latched by the Mach-DSP. (Technically this is called
“active-high, late frame sync” because the sync signal coincides ith data reception.)
Once the Frame Sync line has been detected high, it can remain high during the next 18
clocks, or it may be brought lo again. In any event, the Frame Sync line must be
brought lo by clock number 20, as sho n in the diagram above, other ise a Frame
Sync Error ill occur, and data ill not be communicated correctly. In essence, all of
this means that the data is “framed” in 20-clock sequences.
The Clock line can be any frequency up to a theoretical maximum of 25MHz, ith any
reasonable duty cycle. The data frames described above may occur in sequence, one
after another (called “coherent frames”), or they may be sporadic (called “isolated
frames”). If they are sporadic, the Clock line may continue clocking in bet een data
frames, or it may be quiescent (preferably held in a lo state). In all cases, hether the
clock is operational or not, the Frame Sync line must be held lo hen data is not sent.
The “frame rate” may be anything that the Clock and Frame Sync signals allo –
ranging from slo er than one frame per hour up to a theoretical maximum of 1,250,000
frames per second. The data communicated via this serial port is absorbed by the
Mach-DSP at the rate that it is sent, and – unless Synchronous Sampling is selected (as
described several pages belo ), there is no attempt to synchronize the Mach-DSP’s
servo sample clock (typically 100kHz to 300kHz) to the serial port signals.

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You ill note that 19-bits of data per axis (and per returned status) are communicated
using this protocol, although the entire sequence requires 20 clocks. And although
parity is not used by this protocol, some data integrity is provided by “Control Bits”.
You ill also note that the first three bits received by the Mach-DSP are designated “C2,
C1, C0”. These first three bits are called “control bits”, and they designate the function
of the data that is contained in the bits that follo . The table belo describes the control
bits and associated functions:
Table 3.2c: Control Bit Definitions
Control Bits
[2:0]
Function
000 (reserved for future use)
001 16-bit position data follo s
010 (reserved for future use)
011 (reserved for future use)
1xx 18-bit position data follo s
As sho n in the table, only Control Bit patterns 001, and 1xx are presently used,
designating either 16-bit or 18-bit position commands, and therefore there is room for
future expansion as ell as flexibility to implement custom protocols for individual
clients.
For 16-bit position data, a value of 0 (all bits cleared) normally represents the far-left
and far-bottom of the scan field; a value of 32768 represents the middle of the scan
field; and a value of 65535 (all bits set) normally represents the far-right and far-top of
the scan field.
For 18-bit position data, a value of 0 (all bits cleared) normally represents the far-left
and far-bottom of the scan field; a value of 131072 represents the middle of the scan
field; and a value of 262143 (all bits set) normally represents the far-right and far-top of
the scan field.
Of course the relationship of the data to the polarity of axis motion (insomuch as far-left
/ far-right as ell as far-bottom / far-top) depends on hether you are using a left-
handed or right-handed X-Y mount, and each axis may be inverted by changing the
“Input Scale” on the Mach-DSP application soft are, as described in section 7.3.
XY2-100 Status Return signal
The Mach-DSP includes a single serial port line (the RST signal located on the Control
Panel Serial Interface connector), hich may be used to communicate status data back
to the microprocessor-based equipment. Presently this is not implemented and is
reserved for future use. Note that there is great inconsistency among XY2-100-based
equipment on the use (and even presence) of the Status signal.

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FB4 rotocol (only available in certain Mach-DSP firmware versions)
The FB4 protocol combines both X and Y into a single 32-bit data ord, ith X being
the most significant 16-bits, and Y being the least significant 16-bits as sho n belo .
As is the case ith XY2-100, signals that are sent to the Mach-DSP must change on the
lo -to-high transition of the clock; and signals are observed by the Mach-DSP on the
high-to-lo transitions of the clock. Belo is an oscilloscope screen shot sho ing the
simplest implementation of the FB4 protocol. Yello is the clock. Pink is data. Blue is
Frame Sync. The numeric data representation is the same as XY2-100. In the picture
belo , the most significant bits for both X and Y are high, and the rest of the bits are
lo . This represents +32768, hich is equivalent to the center of the scan field.
Once the Frame Sync has been detected lo , it can remain lo during the next 31
clocks, or it may be brought high again after the first clock as sho n above. In any

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event, Frame Sync must be brought high by clock number 32, as sho n in the diagram
above, other ise a Frame Sync Error ill occur, and data ill not be communicated
correctly. In essence, all of this means that the data is “framed” in 32-clock sequences.
The Clock line can be any frequency up to a theoretical maximum of 25MHz, ith any
reasonable duty cycle. The data frames described above may occur in sequence, one
after another (called “coherent frames”), or they may be sporadic (called “isolated
frames”). If they are sporadic, the Clock line may continue clocking in bet een data
frames, or it may be quiescent (preferably held in a lo state). In all cases, hether the
clock is operational or not, the Frame Sync line must be held high hen data is not sent.
The “frame rate” may be anything that the Clock and Frame Sync signals allo –
ranging from slo er than one frame per hour up to a theoretical maximum of 781,250
frames per second. The data communicated via this serial port is absorbed by the
Mach-DSP at the rate that it is sent, and – unless Synchronous Sampling is selected (as
described belo ), there is no attempt to synchronize the Mach-DSP’s servo sample
clock (typically 100kHz to 300kHz) to the serial port signals.
You ill note that 16-bits of data per axis are communicated using this protocol, and the
entire sequence requires 32 clocks. X-axis data is first ith the MSB during clock
number 1. Y-axis data is next ith MSB during clock number 17.
FB4 Position return data
The FB4 protocol uses one of the data lines to return the XY position that as read by
the Analog to Digital converters. And unless Synchronous Sampling is selected (as
described belo ), there may be a several sample delay bet een the instantaneous
position and the value of the position that is communicated by the return signal.
Synchronizing the servo sam ling with data communication
It may be desirable to synchronize the servo sampling ith the actual serial data
communication. This allo s for consistent and fresh position data to be returned from
the servo, and prevents aliasing of the digital command and position signals that
other ise occur hen the servo sampling happens asynchronously to serial data.
Before synchronous sampling can be enabled, the Digitizing sample rate must be set
in accordance ith the expected serial data frame rate, and the servo tuning must be
optimized for that particular sample rate. The Digitizing sample rate is found in the
Digitizer parameters section of the Pangolin only tab. We ould also recommend
testing bi-directional data communication, and making sure that everything is orking
perfectly, before enabling synchronous sampling.
When you are ready, check the box Synchronize sampling with Serial Input Frame
Sync. When this is done, the Analog to Digital Converters on the Mach-DSP ill start
their conversion cycle on the rising edge of Frame Sync, and serial communication
begins on the falling edge of Frame Sync.

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Note that it takes roughly 5.75uS for the analog-to-digital conversion to be completed,
and for the data to be read and processed. If Frame Sync is brought lo after 5.75uS
(as sho n in the screen shot belo ), then the position data that is returned ill
correspond ith the immediately preceding rising edge of the Frame Sync signal.
In this screen shot, Frame Sync is brought high for around 6.1 microseconds, then
Frame Sync is brought lo and serial communication commences. The command input
data and the returned position data are both communicated at the same time, and on
the same edges of the clock.
The screen shot above sho s 100kHz sample rate, hich is reasonable for most
applications. To provide for synchronized sampling as ell as complete data
transmission during the present frame, the clock rate needs to be at least 8.3MHz for a
100kHz sample rate.
Future Ex ansion and Alternative Protocols
It should be obvious that there is a great deal of flexibility built into the Mach-DSP, and a
variety of custom applications and alternatives are possible. The number of bits used
and the polarity of Clock and Frame Sync signals are all easily changed. Please contact
us if you have special requirements, since they may be accommodated via firm are
updates, hich are easily performed by users in the field.

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3.2c Differential Signaling (XY2-100) Interface Daughterboard
An optional Differential Signaling Interface Daughterboard can be fitted onto the Mach-
DSP, providing XY2-100-compatible differential signaling ith RS-422 voltage levels.
This allo s the Mach-DSP to be used ith standard laser-marking-style laser controllers
that output XY2-100. This is sho n in the picture belo , ith the laser-marking
controller appearing in the lo er left of the picture and Mach-DSP in the upper-right.
The XY2-100 interface daughterboard uses a 26-pin IDC connector, hich can be
connected through a ribbon cable directly to a laser-marking controller that also uses a
26-pin IDC connector. Alternatively, the ribbon cable can be terminated in a DB-25
connector, as as typical many years ago hen the XY2-100 standard as developed.
When it is desirable to run the Mach-DSP from po er sent through the XY2-100 cable,
you should connect the po er ires from 4-pin po er connector (discussed in section
3.1 of this manual) to the Red, Green, and Blue terminals on the right side of the
daughterboard (or terminals designated +, -, and ground if they’re not colored). Red
indicates positive voltage, Green indicates ground, and Blue indicates negative voltage.
Be sure to select a Digital Input as the Input Source, as discussed in section 7.3.

Mach-DSP User’s Manual
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3.3 Status and Control signals
The status/control signal interface is located in the left side of the board near the front.
System I/O includes optically-isolated inputs and outputs facilitated through optical
isolators having part number MOCD207M. The pin functions are described in Table 3.3:
Table 3.3: Status / Control Interface
Pin Function
1 Collector of isolated output 1
2 Collector of isolated output 2
3 Cathode of isolated input 1
4 Cathode of isolated input 2
5 Emitter of isolated output 1
6 Emitter of isolated output 2
7 Anode of isolated input 1
8 Anode of isolated input 2
Mating Connector Housing: MOLEX Micro-Fit Jr: 0430250800
Mating Connector Pins: 0430300001 through 0430300012
S ecified Wire Size: AWG #20-#30, depending on pin type
O tically-isolated In uts
The Mach-DSP features t o separate TTL-level inputs, facilitated as LED inputs of
optical isolators. These inputs that can be programmed to respond in a variety of ays,
using the “Control” tab of the Mach-DSP PC application. For example, these inputs may
be used as an external “SERVO ENABLE” signal that ill enable the servo driver hen
the laser Machine is ready for use, but disable the servo driver and place it in standby
other ise. Another example use is to use one or both of these inputs to select scanner-
tunings on the fly. (Although the isolation offered is greater than 500 volts, you
should not exceed greater than +/- 6V across the Anode/Cathode terminals.)
O tically-isolated Out uts
The Mach-DSP also features t o separate “TTL” outputs, facilitated as open-collector
phototransistor outputs of optical isolators. These TTL outputs that can be programmed
to respond in a variety of ays, using the “Control” tab of the Mach-DSP PC application.
For example, one or both of these outputs can be used as a “Fault” indication – to
indicate that the servo has encountered an over-temperature or over-position fault.
Another example use is to use one or both of these outputs as a “Settled” indicator, to
indicate hen the servo position error has reached a suitably lo value, indicating that
the mirror has reached its commanded position. (Although these “TTL” out uts will
ty ically be used with TTL-level voltages, they su ort u to 30V across each
hototransistor, and u to 150mA flowing through each hototransistor.)

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3.4 Control Panel Serial interface
The Mach-DSP includes a 3.3V-TTL-level RS-232 serial port, hich can be used to
select and adjust scanner tunings as ell as monitor the overall health of the servo
driver. This connector is located on the left / front side of the board. The connector pin
functions are provided in Table 3.4:
Table 3.4: Control Panel Serial Interface
Pin Function
1 +5V Output
2 RXD (data to ard Mach-DSP)
3 TXD (data from Mach-DSP)
4 Ground
5 (reserved / XY2-100 Status)
Mating Connector Housing: MOLEX SL: 0050579405
Mating Connector Pins: 0016020082 or 0016020088
S ecified Wire Size: AWG #22-#30, depending on pin type
As expressed above, the RXD and TXD signals use 3.3V signal levels. These signals
are protected by series resistors and Schottky diodes, and therefore applying higher
voltages, or applying voltages hile po er is not applied to the Mach-DSP should not
cause any harm.
This manual does not include details of the communications protocol used by this
connector, but the communications protocol is available to OEMs ho agree to the
terms of our NDA.
Note that in addition to serial communications signals found on this connector, the
Mach-DSP also provides regulated +5V as ell. This may be used to po er an external
control panel including OLED display, or it may be used to provide po er for the
optically-isolated TTL inputs or TTL outputs described in the Status / Control Interface
section of this manual.

Mach-DSP User’s Manual
Document Number: MACH-DSP-9021 Page 20
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3.5 est and hermistor interface
The Test and Thermistor interface connector is located on the right / front side of the
board. This connector provides 1K-resistor-buffered analog output signals that may be
used during servo tuning, and may also be monitored by external equipment if desired.
This connector may also be used to connect a thermistor as described belo . The
connector pin functions for the test interface connector are provided in Table 3.5.
Table 3.5: Test Interface
Pin Function
1 Ground
2 X-axis Position (not scaled)
3 X-axis Command input (after filter)
4 X-axis Motor drive current (1 V/A)
5 X-axis AGC drive voltage (negative)
6 Ground (usually used for thermistor)
7 User-defined analog output 1
8 User-defined analog output 2
9 User-defined analog output 3
10 Ground
11 Y-axis Position (not scaled)
12 Y-axis Command input (after filter)
13 Y-axis Motor drive current (1 V/A)
14 Y-axis AGC drive voltage (negative)
15 NTC Thermistor (10K β=3300 nominal)
16 User-defined analog output 4
17 User-defined analog output 5
18 User-defined analog output 6
Mating Connector Housing: MOLEX Micro-Fit Jr: 0430251800
Mating Connector Pins: 0430300001 through 0430300012
S ecified Wire Size: AWG #20-#30, depending on pin type
Position, Command, Current and AGC signals
The Test Interface connector includes a number of signals that are referred to as
“analog”, but the only truly analog signals are the Position, Command, Current and AGC
outputs for both the X- and Y-axes. These are measured and processed purely in the
analog domain. As such, they offer maximum resolution in both time and range.
The Position signal has a scale factor that varies some hat from scanner to scanner,
but tends to be approximately 2.45 mechanical degrees per volt for systems that are not
customized. The Command signal output is a direct reflection of the Mach-DSP analog
command input. The Current signal has a fixed scale factor of 1-volt-per-amp. The AGC
signal is a reflection of the voltage seen by the galvo position sensor LED driver.