Homann Designs DC-03 User manual

DigiSpeed-GX™ - Users Guide Page 1
Updated: 12. December 2006
DigiSpeed-GX™ DC-03
Is lated C ntr l V ltage Generat r
User’s Guide
DigiSpeed-GX™ PCB Ver:1.0
Firmware Ver: 1.0
Mach3 Ver: 1.84
C pyright 2006 © H mann Designs Revisi n 0.1

DigiSpeed-GX™ - Users Guide Page 2
H mann Designs
20 View St
HIGHETT VIC, 3190
AUSTRALIA
info@homannde ign .com
http://www.homannde ign .com
C pyright 2006 © H mann Designs. All rights reserved.
No part of thi publication may be reproduced, tran mitted, tran cribed, tored in a retrieval
y tem, or tran lated into any language or computer language, in any form or by any mean ,
electronic, mechanical, magnetic, optical, chemical, manual or otherwi e, without the prior
written permi ion of Homann De ign .
Disclaimer
Homann De ign make no repre entation or warrantie with re pect to the content
hereof and pecifically di claim any implied warrantie or merchantability or fitne for any
particular purpo e. Information in thi publication i ubject to change without notice and
doe not repre ent a commitment on the part of Homann De ign .
Feedback
We appreciate any feedback you may have for improvement on thi document. Plea e end
your comment to info@homannde ign .com
Trademarks
DigiSpeed™ and DigiSpeed-GX™ are trademark of Homann De ign . All other brand and
product name mentioned herein are trademark , ervice mark , regi tered trademark , or
regi tered ervice mark of their re pective owner and hould be treated a uch.
C pyright 2006 © H mann Designs Revisi n 0.1

DigiSpeed-GX™ - Users Guide Page 3
Table f C ntents
1 Introduction...................................................................................................................................... 5
1.1 Content .....................................................................................................................................5
1.2 Overview................................................................................................................................... 6
2 Option ............................................................................................................................................. 7
2.1 5Vdc – 15Vdc i olated DC-DC Converter................................................................................7
3 Feature .............................................................................................................................................8
4 Board De cription.............................................................................................................................9
4.1 Introduction............................................................................................................................... 9
4.2 Mode Indication LED..............................................................................................................10
4.2.1 Mode Indication.............................................................................................................. 10
4.2.2 Input Activity Indication................................................................................................. 10
4.3 Output Attenuation Trimpot.................................................................................................... 11
4.4 Output Voltage Selection JP1..................................................................................................11
4.5 Mode Selection Jumper Block JP2..........................................................................................12
5 Quick Start Guide – PWM Mode................................................................................................... 13
5.1 What you need.........................................................................................................................13
5.2 Mach3 Configuration Setup.................................................................................................... 13
5.2.1 Port Setup........................................................................................................................14
5.2.2 Spindle Setup Tab........................................................................................................... 14
5.3 Power to the DigiSpeed-GX....................................................................................................15
5.4 Connect the PWM Signal........................................................................................................ 15
5.5 Conclu ion...............................................................................................................................16
6 In tallation...................................................................................................................................... 16
6.1 DC Motor Speed Controller hou ing.......................................................................................16
6.2 Wiring in tallation................................................................................................................... 16
6.2.1 Motor Controller Connection..........................................................................................17
6.2.2 Initial Te ting.................................................................................................................. 17
6.2.2.1 Attenuation Trimpot Speed Control........................................................................ 17
6.2.2.2 Computer Speed Control......................................................................................... 17
7 Operation........................................................................................................................................ 19
7.1 Operation Mode ..................................................................................................................... 19
7.1.1 Analog Input Mode......................................................................................................... 19
7.1.2 PWM Input Mode........................................................................................................... 19
7.1.3 Attenuation Trimpot........................................................................................................20
8 Board Dimen ion .......................................................................................................................... 21
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DigiSpeed-GX™ - Users Guide Page 4
Index f Tables
Table 1: Mode Select Jumper Block.................................................................................................. 12
Table 2: DigiSpeed-GX™ - Breakout board Connection .................................................................14
Table 3: Mode Selection Jumper ...................................................................................................... 19
Illustrati n Index
Illu tration 1: Mach3 Port Setup.........................................................................................................14
Illu tration 2: Mach3 Spindle Setup Tab............................................................................................15
Illu tration 3: PCB Dimen ion and Layout.......................................................................................21
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DigiSpeed-GX™ - Users Guide Page 5
1 Intr ducti n
Thank you for purcha ing Homann De ign ' DigiSpeed-GX™ Isolated Voltage interface
unit. The DigiSpeed-GX™ provide a way for controlling DC motor peed controller and
other device that accept a 0-5Vdc, 0-10Vdc, 0-15Vdc voltage ignal
Thi document i a U er' Guide that de cribe the operation of the DigiSpeed-GX™. The
document contain information on how to u e and integrate the board into your own
y tem .
1.1 Contents
The box received when ordering the DigiSpeed-GX™ contain the following:
•DigiSpeed-GX™ i olated voltage interface unit.
•2 x 0.1” jumper .
•4 x 4mm pla tic PCB tand-off .
C pyright 2006 © H mann Designs Revisi n 0.1
*** WARNING ***
The KB Electronics DC speed controller circuit, and other similar
speed controllers as found in Asian imported mini lathes and mini
mills are at mains oltage potential. This oltage is lethal. Do not
attempt to do this con ersion if you are not qualified to do so.
Confidence is no replacement for qualification!
If you feel that this project is beyond your abilities to SAFELY
complete, we can install the unit for you. Please contact us for details
Please ensure you read the complete manual before attempting to
install or use this de ice.

DigiSpeed-GX™ - Users Guide Page 6
1.2 Overview
The DigiSpeed-GX I olated Voltage Interface Unit i de igned to allow device uch a
the Gecko G-100 motion controller and computer CNC program uch a Mach2,
TurboCNC and other CNC program to control device that require an i olated DC control
voltage.
DigiSpeed-GX i de igned primarily for u e with KB Electronic tyle DC motor
controller , uch a the KBIC-120. Thi i the type of controller found in the Sherline
Mill and Lathe . DigiSpeed-GX will work with other type of DC motor controller
uch a tho e found in the A ian imported mini lathe and Mill .
The DigiSpeed-GX™ i al o well uited for u e with VFD uch a the Automation Direct
GS2 erie and other motor peed controller which accept a 0-5Vdc, 0-10Vdc peed
control voltage.
The form factor of the DigiSpeed-GX PCB ha been de igned for ea y in tallation. Due
to it compact ize, it can al o be in talled unobtru ively into many of the exi ting peed
controller or CNC controller enclo ure .
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DigiSpeed-GX™ - Users Guide Page 7
2 Opti ns
The DigiSpeed-GX™ i a ver atile unit. It ha an on-board LED indicator, mode elect
jumper , and an attenuation multi-turn trim-pot The board i de igned to be in talled into
exi ting motor peed controller hou ing , external CNC hou ing or other enclo ure .
2.1 5Vdc – 15Vdc isolated DC-DC Converter.
Depending on the in tallation, the device being controlled by the DigiSpeed-GX™ may
not be able to provide the 10Vdc upply required by the i olated analog circuitry. In uch
ituation , the optional On-board 5Vdc - 15Vdc i olated DC-DC converter may be u ed to
provide the required upply.
Note: The DigiSpeed-GX™ Attenuation trimpot may be used to scale the output voltage to 0- 0Vdc,
or to a voltage that is required by the device being controlled by the DigiSpeed-GX™ .
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DigiSpeed-GX™ - Users Guide Page 8
3 Features
The main feature of the DigiSpeed-GX controller are;
•Controlled by a RISC Microchip micro-controller.
•PCB
oFR4 Material
oDouble Sided, Plated through hole
oSilk-Screened on Component Side
oSolder Ma k on Both Side
•Small PCB footprint 2”(L) x 1”(W)
•Four 4mm mounting hole ( upplied with matching tand-off )
•5V dc XXXmA power requirement .
•Opto-i olation between the computer logic Voltage and the analolg output control voltage .
•Maximum DC Speed controller voltage for the control upply of 15Vdc
•10 bit re olution providing more than 1000 tep from 0 to Max Output voltage.
•Four method to control motor peed.
o0-5V analog Voltage
oPWM - A low frequency PWM ignal. (2Hz – 100Hz )
oOn-Board multi-turn trimpot
•Output Control Voltage Attenuator.
•SMT LED indicating the mode and tate of the DigiSpeed-GX controller.
•Pluggable 3.5mm terminal block connector for ea y in tallation and maintenance.
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DigiSpeed-GX™ - Users Guide Page 9
4 B ard Descripti n
4.1 Introduction
The DigiSpeed-GX controller provide the capability to
control a device uch a the the pindle peed of a DC or AC
motor via computer control
May of the device that the DigiSpeed-GX i de igned to
work with uch a the KBIC-120 controller upplied by KB
Electronic , u e a “Hot Ground” circuitry. That i , the
reference voltage for etting the peed are at MAINS
POTENTIAL voltage. Thi voltage i dangerou and can be
lethal.
Thi tyle of controller u e a control voltage, u ually in the
0 –10Vdc range to control the motor peed from 0 – max
peed. In reality, thi voltage can be anywhere in the range
of 5Vdc to 15vdc. The maximum output voltage of the
DigiSpeed-GX and thu the peed of the motor can be
limited by an attenuation trim-pot that reduce thi control
voltage upply.
AC motor controller are u ually Variable Frequency Drive (VFD) and have terminal for
the connection of an external manual control potentiometer, or a 0-5Vdc, 0-10Vdc control
voltage.
The DigiSpeed-GX circuitry i e entially in two part . One part contain low voltage
logic level circuitry that include a micro controller and interface to the PC or controlling
device. It i upplied by 5Vdc that i referenced to the controlling device ground. The
other part of the DigiSpeed-GX circuitry i connected to the DC Speed controller
control circuitry. Thi part i at MAINS POTENTIAL.
The two part of the circuitry are eparated by opto-i olation. Thi en ure that the
dangerou MAINS POTENTIAL voltage are kept away from the low level logic
circuitry. The two part of circuitry mu t never be connected together. If it happen , a
cata trophic failure of the DigiSpeed-GX circuit and your PC will occur.
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DigiSpeed-GX™ - Users Guide Page 10
The DigiSpeed-GX controller provide a control voltage in place of the control voltage
provided by the manual peed control potentiometer. Thi voltage can be varied from 0V
to 100% of the maximum control voltage by computer oftware.
There are 1023 tep from 0 to the maximum control voltage. If your maximum pindle
peed i 6000 rpm, thi effectively provide for a 6-rpm re olution in controlling pindle
peed.
4.2 Mode Indication LED
The DigiSpeed-GX controller contain a SMT LED that i u ed to indicate the input
mode that ha been elected and when activity on the input i pre ent.
4.2.1 M de Indicati n
The DigiSpeed-GX controller u ed the indicator LED to how which input mode i
elected. It doe thi by fla hing the LED on power up a de cribed below;
•LED Off – Thi indicate that there i no 5Vdc power upplied to the DigiSpeed-
GX .
•Single Flash – Indicate that the DigiSpeed-GX i powered in Analog input
Mode.
•Double Flash – Indicate that the DigiSpeed-GX i powered in PWM input
Mode.
•Triple Flash – Indicate that the DigiSpeed-GX i powered in Multi-turn
Trimpot input Mode.
4.2.2 Input Activity Indicati n
The DigiSpeed-GX controller u e the LED to indicate when there i activity on the
input. Thi activity i a de cribed below;
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***YOU HA E BEEN WARNED***
DO NOT GROUND THE MAINS POTENTIAL SIDE OF THE
CIRCUITRY

DigiSpeed-GX™ - Users Guide Page 11
•LED Off – Thi indicate that there i no 5Vdc power upplied to the DigiSpeed-
GX .
•Lazy RED Double Flash – Indicate that the DigiSpeed-GX i powered on, and
there i no activity on the input ource.
•Fast RED Flash – Indicate that the DigiSpeed-GX i powered, and there i
activity on the input ource.
4.3 Out ut Attenuation Trim ot
The DigiSpeed-GX controller contain an Output Attenuation Trimpot. The purpo e of
thi i to attenuate or reduce the full cale output voltage of the controller. Thi may be
u ed to reduce the maximum peed of a pindle.
By turning the crew in the 11 turn trimpot VR1, in a Counter-Clockwi e direction, the
output voltage will be reduced, or attenuated.
Some VFD and motor controller require a 0 – 5Vdc voltage to control pindle peed, yet
provide a 10Vdc voltage upply. In thi in tance, the attenuator may be u ed to reduce the
10V control voltage to 5V a required by the controller.
4.4 Out ut Voltage Selection JP1
Note: This jumper is only fitted when the optional DC-DC isolated voltage generator is fitted.
The DigiSpeed-GX controller contain an Output voltage election jumper, JP1. The
purpo e of thi i to elect the ource of the i olated voltage that i generated.
If the jumper i fitted between pin 1-2 (toward the DC-DC generator) then the
Generator 15Vdc voltage will be u ed. In thi in tance there i no need to connect the
motor controller to pin AV+ on connector J2
If the jumper i fitted between pin 2-3 (away from the DC-DC generator) then the voltage
upplied by the DC motor controller via connector J2, pin AV+ will be u ed.
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DigiSpeed-GX™ - Users Guide Page 12
4.5 Mode Selection Jum er Block JP2
The DigiSpeed-GX can operate in a number of mode , depending on the type of control
ignal that i provided by your CNC oftware and or controller. The mode i elected via
the mode election jumper a hown in the picture below;
Jumper JP2 con i t of a two jumper . MSI i the jumper clo e t to the Input Terminal
block J1. MS2 i immediately below MS2.
Jumper Function Position
MS1 Mode
Select
Top
MS2 Mode
Select
Bottom
Table 1: Mode Select Jumper lock
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DigiSpeed-GX™ - Users Guide Page 13
5 Quick Start Guide – PWM M de
Thi ection i intended to allow you to quickly etup and verify the operation of your
DigiSpeed-GX™ controller with Mach3 for u e in PWM mode. Initially, thi will be done
with the DigiSpeed-GX™ unit being connected to computer but not your Motor Drive.
Once you are familiar with the operation of the DigiSpeed-GX' operation, it can then be
connected to the motor drive.
The DigiSpeed-GX circuitry i e entially in two part . One part contain low voltage
logic level circuitry that include a micro controller and interface to the PC via the parallel
port. It i upplied by 5Vdc that i referenced to the PC parallel port ground. The other part
of the DigiSpeed-GX circuitry i connected to the DC Speed controller control circuitry.
Thi part i at MAINS POTENTIAL.
The quick tart etup will verify the connection to the Microproce or and logic ide of the
DigiSpeed-GX™ controller.
5.1 What you need
To get tarted, you need:
•DigiSpeed-GX™ controller.
•Breakout board or other mechani m for connecting the DigiSpeed-GX™ control
line to the Computer Printer port.
•A PC with a printer port and Mach3 in talled and running.
Thi quick tart etup i done with the DigiSpeed-GX™ unit itting on the bench and NOT
connected to your Motor controller.
Mach3 control the DigiSpeed-GX™ in PWM mode only. Therefore you need to place
jumper JP1 into the mode election jumper block.
5.2 Mach3 Configuration Setu
The example etup de cribe how Mach3 i configured for the DigiSpeed-GX™. Your
configuration may differ depending on what Printer Port number you are u ing, and what
pin in the port are connected to which DigiSpeed-GX™ pin .
For thi example, printer port 2 i being u ed with the port pin connected a hown in
Table 2 below.
Note :
1. It is advisable to use a breakout board between the Printer port and the DigiSpeed-GX™.
2. The 5V supply for the DigiSpeed-GX™ must be obtained from the breakout board, as it cannot be
supplied from the printer port.
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DigiSpeed-GX™ - Users Guide Page 14
Signal Printer
Port Pin
Number
PC
Input/Out
put
DigiSpeed-GX
J Pins
PC Parallel Port GND (0V) 18-25 - GND
PWM 1 Out VIn
5Vdc with re pect to Pin 1 - - +5V
Table 2: DigiSpeed-GX™ - reakout board Connections
5.2.1 P rt Setup
From the Options menu
in Mach3, elect the
Ports & Pins Setup
item. A hown in
Illu tration 1 below,
Port 2 i enabled and i
et to the default printer
port addre 0X378.
The other item on thi
page are not concerned
with the DigiSpeed-
GX™ Setup.
5.2.2 Spindle Setup Tab
The Spindle etup tab i u ed to configure variou option regarding the Spindle operation.
A hown in Illu tration 2 below, the following item are configured:
•Motor Control – A hown below, the following item are etup:
•The U e 'Spindle Motor Output' check box i ticked.
•The 'PWM Control' check box i ticked.
•The PWM ba e frequency i et to 50.
•The minimum PWM % i et to 0
•Pulley ratio – The maximum pindle peed for the pulley ratio you have are et up
to allow Mach3 to calculate the required PWM percentage.
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Illustration 1: Mach3 Port Setup

DigiSpeed-GX™ - Users Guide Page 15
Thi now conclude the configuration of the Mach3 oftware for the DigiSpeed-GX™. The
next tep i to hook up the unit to your breakout board for te ting.
5.3 Power to the DigiS eed-GX
The fir t tep in the in tallation i to provide 5V power to the DigiSpeed-GX™ controller.
Wire DigiSpeed-GX™ J1- GND pin to a logic ground terminal on your CNC controller
breakout board. Thi logic ground i the ame a the PC printer port 0V potential, found on
pin 18 to 25 of your printer port.
Wire DigiSpeed-GX™ J1-+5V to a 5Vdc upply on your CNC controller' breakout
board. Thi need to be 5Vdc with re pect to the PC printer port ground.
Turn on your CNC controller. Thi hould provide the 5Vdc upply to the DigiSpeed-
GX™. Verify thi i the ca e, by checking that the Mode Indicator LED i fla h a low
double fla h. If not, turn off the CNC controller and check the wiring.
5.4 Connect the PWM Signal
Wire DigiSpeed-GX™ J1-Vin to pin 1 of the printer port via your CNC controller'
breakout board.
You can now te t that the PWM peed value i being received by the DigiSpeed-GX™. Set
the pindle peed to zero typing it into the peed DRO, or entering the command 'S 0' into
the MDI window .
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Illustration 2: Mach3 Spindle Setup Tab

DigiSpeed-GX™ - Users Guide Page 16
Now enter a pindle peed of 1000 into the DRO and enable the pindle. You hould now
ob erve the DigiSpeed-GX™ Mode Indicator LED perform a continuou Red fa t fla h.
Thi indicate that the DigiSpeed-GX™ i enabled and i generating an analog control
voltage on the output.
5.5 Conclusion
You hould now have your DigiSpeed-GX™ operating correctly with Mach3. You are now
ready to in tall the unit into your Motor Speed controller' enclo ure, your CNC controller
or a eparate enclo ure.
6 Installati n
Before attempting the in tallation plea e read the entire manual. If you are un ure of
anything, do not do the in tallation. Get help from omeone who i qualified for thi type
of work. I am not re pon ible for damage or injury re ulting from the in tallation or u e of
thi device.
It i advi able to integrate the The DigiSpeed-GX with your control oftware before
in talling and connecting it to your Motor Controller. The unit i powered from a breakout
board. Therefore it i po ible to te t and become familiar with it' operation prior to
connecting it to a motor controller.
The board ha indicator LED that provide tatu of what i occurring. The e can be u ed
to a i t in the integration.
The DigiSpeed-GX may be mounted into an exi ting motor controller enclo ure or
external enclo ure . The hardware in tallation i dependent on what you are in talling the
DigiSpeed-GX into. The phy ical in tallation i fir t covered in the ection below,
followed by the electrical in tallation.
6.1 DC Motor S eed Controller housing
If the DigiSpeed-GX™ i to be in talled into an exi ting Motor peed controller hou ing,
en ure that there i ufficient pace to afely in tall the DigiSpeed-GX™.
Refer to the PCB layout and dimen ion diagram in determining the po ition of hole for
mounting. The unit may be mounted u ing the 4 tand-off provided.
6.2 Wiring installation
Once the DigiSpeed-GX controller i in talled into a hou ing the following wiring i
required.
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DigiSpeed-GX™ - Users Guide Page 17
6.2.1 M t r C ntr ller C nnecti n
The DigiSpeed-GX i connected to the motor controller via the three terminal pluggable
connector J2.
•The terminal labeled A + connect to the potentiometer po itive voltage
connector on the peed controller.
•The terminal labeled out connect to the potentiometer connector on the peed
controller.
•The terminal labeled AGnd connect to the potentiometer control voltage on the
peed controller.
The e three connection plug into your peed controller in place of your exi ting manual
peed potentiometer. Unle you are u ing a voltage i olation board the e lead are at
***MAINS OLTAGE POTENTIAL ***. They can cau e eriou injury or death. Do
not connect any earthed te t equipment to thi terminal block a it i at main potential.
6.2.2 Initial Testing
6.2.2.1 Attenuation Trimpot Speed Control.
To te t the DigiSpeed-GX control manually via the attenuation trimpot VR1:
1. Turn off the Motor Speed controller and the CNC controller .
2. Set the DigiSpeed-GX mode to Attenuation Trimpot by in erting jumper MS1
and MS2.
3. Turn the attenuation trimpot Anti-Clockwi e eleven complete turn .
4. Power up the DigiSpeed-GX .
5. Turn on the Motor Speed controller. En ure that there i 5Vdc power applied to the
DigiSpeed-GX. You can verify thi by the Lazy Double Fla h of the LED
illuminated on the DigiSpeed-GX.
6. Slowly turn the trimpot Clockwi e unit the required maximum pindle peed i
reached.
6.2.2.2 Computer Speed Control.
To te t the DigiSpeed-GX control from Mach3:
1. Turn off the Motor Speed controller and the CNC controller .
2. Set the DigiSpeed-GX mode to :PWM by in erting jumper MS1 only.
3. Power up the DigiSpeed-GX .
4. Turn on the Motor Speed controller. En ure that there i 5Vdc power applied to the
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DigiSpeed-GX™ - Users Guide Page 18
DigiSpeed-GX. You can verify thi by the Lazy Double Fla h of the LED
illuminated on the DigiSpeed-GX.
Run through the te t detailed in the Quick Start Guide ection with the under tanding that
the pindle i not powered and operational.
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DigiSpeed-GX™ - Users Guide Page 19
7 Operati n
7.1 O eration Modes
The DigiSpeed-GX™ ha four operational mode , elected by jumper MS1, MS2 in
jumper block JP2. The election of the mode i de cribed below.
Mode MS MS2
ANALOG Removed Don't Care
PWM In talled Removed
Attenuation Trimpot In talled In talled
Table 3: Mode Selection Jumpers
The election of the mode i done at power up initialization.
Note: If the mode selection jumpers are modified after the unit is powered up, the new mode will
not take effect until the power is cycled.
Each of the mode i di cu ed in detail below.
7.1.1 Anal g Input M de
In thi mode the DigiSpeed-GX controller accept an analog 0-5Vdc ignal. 0Vdc
repre ent 0%, varying to 5Vdc which repre ent 100% of maximum pindle peed.
Thi will provide 1023 peed increment from 0 to 100% of maximum pindle peed.
With the DigiSpeed-GX module upplied with power, and no analog ignal i pre ent,
the LED will be a Red low double fla h. Thi indicate that the pindle i active but the
peed i et to 0 %. Then, when an analog voltage ignal i pre ent, the LED will be a fa t
continuou fla h, indicating that the pindle i active and the peed i et to a value greater
than 0 %.
7.1.2 PWM Input M de
In thi mode the DigiSpeed-GX controller accept an “Active Low” Pul e Width
Modulation ignal. The duty cycle of thi ignal repre ent 0 to 100% of maximum pindle
peed.
The PWM ignal period can be in the range of 2Hz to 50Hz. The optimum period i 50Hz.
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DigiSpeed-GX™ - Users Guide Page 20
Thi will provide 1023 peed increment from 0 to 100% of maximum pindle peed.
With +5V i upplied to the DigiSpeed-GX module, and no PWM ignal i pre ent, the
LED will be a Red low double fla h. Thi indicate that the pindle i active but the peed
i et to 0 %. Then, when a PWM ignal i pre ent, the LED will be a fa t continuou
fla h, indicating that the pindle i active and the peed i et to a value greater than 0 %.
7.1.3 Attenuati n Trimp t
In thi mode the DigiSpeed-GX controller u e the attenuation trimpot to generate the
oiutput voltage. It a ume there i a full cale analog voltage input and then attenuate it
to produce 0% to 100% of the output voltage.
With +5V i upplied to the DigiSpeed-GX module, the LED will be a low double fla h
when the trimpot i et to maximum attenuation by turning the crew fully counter-
clockwi e..
When the attenuation i not et at maximum, the LED will fla h at a fa t rate, with the
output voltage generated a a percentage of the full cale voltage.
C pyright 2006 © H mann Designs Revisi n 0.1