CNC4PC C11 User manual

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 1/18
C11- MULTIFUNCTION CNC BOARD Rev. 8
User manual Rev. 1
1. Overview
This card has been designed to provide a flexible interface and functions to your
computer projects, by using the parallel port control software. This board provides
a faster way to connect devices and reduce the possibility of wiring errors.
2. Features
•Fully optosiolated
The card isolates connections to
protect your computer from short-
circuit. An opto-isolator is an
integrated circuit that transmits the
signal through an encapsulated LED
and phototransistor. When the signal
is on, the LED lights up, the
phototransistor captures it and relays
the signal. The signals are transmitted
through light and not through physical
connections. In this way, a power
surge has no way of reaching your
computer. That is the reason why this
card has two power connections. One
power connection is power powering
the circuit that interacts with the PC,
the other connection is for powering
the circuit that interacts with your
CNC system. Extra precautions have
been taken when designing this
circuit, by taking into consideration
the extremely high voltages that
stepper drivers can achieve and lack
of experience that some users could
have in wiring circuits of this kind.
This board keeps the grounds of the
PC isolated from the grounds of the
rest of your CNC circuit.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 2/18
•Support for up to 150 KHz
optoisolation on step and
direction signals.
New on this revision is that the
optoisolation circuit has been
optimized and now supports full
optoisolation at speeds over 150 kHz.
•Built-in Passive Low Pass Filters
for the all signal.
This board includes low pass filters to
reduce the effect of the noise from the
drivers or other devices over the
signals.
•Microcontroller based SCHP.
This board comes with a
microcontroller that allows the
implementation of a complex
algorithm for sampling and analyzing
the SCHP signal.
•All TTL 5VDC signals.
Interface directly with parallel port
interface products and other CNC4PC
cards. 5VDC (TTL) cards are very
common among automation devices.
•Buffered outputs.
All outputs are buffered through the
use of high speed and high current
buffers, with the result that your
devices receive all the power they
need.
•Easy installation of an On/Off
switch. You can control the card
externally.
An On/Off or a Safety Charge Pump
can easily be installed to enable or
disable the card. CNC machines
could be dangerous and, remember,
safety comes first. This card is
provided with an extra pin (EN) that
allows you to control the card
externally by enabling or disabling
outputs. The card must have +5vdc
supplied to the EN terminal to enable
outputs.
•Status LEDs on all inputs and
output connections.
No more guessing. You can SEE all
your signals. Save valuable time and
brainpower for CNCing. To avoid
remaining current to the main load
(driver or other device), all the
indicator LEDs are driven by
independent buffers of the ones that
drive de output.
•Built-in Variable Speed Control.
It has an optoisolated analog 0-
10VDC output that will convert a step
signal into an analog signal that can
be used to command a commercial
VFD. This analog can be adjusted
using on-board potentiometer, so this
board can be adjusted to other
voltages.
•Two Built-in Electromechanical
Relays with NO and NC
positions.
•All pins can be used in a
concurrent manner.
You can use all the input or output
pins in a concurrent manner. For
example, if you are using output pin
#1 to control the Built-in
Electromechanical Relay, you can
also access that signal from the
output pin on the board or from the
DB25 connector for output. Each
connection will not affect the other
current from the other connection.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 3/18
•Has an extra DB25 female
connection for output.
You can use this card to optoisolate
any existing setup just by connecting
this card between your computer and
your current setup. That way, you can
also see and access all your signals.
This makes this card ideal for use
with the Xylotex, HobbyCNC or other
non-optoisolated boards. You only
have to add this board to a DB25
male connection to a male cable.
•Input and output pins with close
by ground connections.
Forget about grounding problems.
Easily connect your pin by using your
close by ground connection. No need
to be an electronics expert to ground
all your stuff. The terminals next to
pins 2-9 can be set to have +5VDC or
GND according to your needs. There
is a jumpers that allows you to select
+5VDC or GND for the COM pins.
•Works directly with popular CNC
hardware and software.
That goes for Geckdrive, DeskCNC or
Rutex and parallel port control
software such as mach2, Linux EMC,
TurboCNC, CNCZeus and other/ (Not
all have been tested).
•Screw-On connections for all
terminals.
You only have to screw-on the wires
to make all your connections.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 4/18
1. Specifications.
DIGITAL INPUT SPECIFICATIONS
Numbers of inputs 5
On-state volta e ran e 2 to 5V DC
Minimum on-state input current 1.1 mA
Typical on-state current 1mA @ 5V DC
Maximum off-state voltaje 0.8V
Maximum off-state current 1.1 mA
Input Impedance (nominal) 4.6 KΩ
Typical si nal delay 2.8uS
DIGITAL OUTPUT SPECIFICATIONS
Number of outputs 12
Maximum output volta e (5V power supply volta e) + 0.5V
Maximum on-state current 50mA
Typical output current 24mA
Maximum off-state voltaje 0.44 V
Typical si nal delay 3uS
Time of transition to hi h impedance state 120mS*
Time passed since a fault in the SCHP signal is detected and the outputs are disabled.
The recommended pulse width for the inputs and outputs is 5us.
Some higher frequencies require the pulses width showed in the below Table.
RECOMMENDED PULSE WIDTH FOR SOME FREQUENCIES
Frequency Recommended pulse width
100KHz 3-5us
150KHz 3us

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 5/18
2. Functional Block Diagrams
4.1 Output simplified functional block diagram
Fig. 1 Simplified functional block diagram for the output.
An initial buffer is used considering the low current a parallel port can sink and
source. Using an RC Low Pass filter followed by a Schmitt Trigger gate help to
reduce the effect of the noise from driver or other devices, eliminating the high
frequency components of the noise and generating a fast changing signal. To
avoid remaining current to the main load (driver), the indicator led is driven by a
different buffer.
4.2 Input simplified functional block diagram
Fig. 2 Simplified functional block diagram for the inputs.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 6/18
3. Wiring diagrams
Different kind of sensors and switches can be connected to inputs board, but this
board support only TTL signal, so if you need to connect devices that generates
12V or 24V signal in some cases is necessary add external resistors.
Note. All inputs have the same configuration. The below wiring diagrams are an example,
any input can be used for the connections.
Fig. 3 Wiring diagram to connect switches.
Fig. 4 Wiring diagram to connect NPN open collector proximity sensors.
For a 24V or 12V sensor, the recommended value for the external resistor R1 is
4.7K Ohm.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 7/18
Fig. 5 Wiring diagram to connect in parallel NPN open collector proximity sensors.
Fig. 6 Wiring diagram to connect NPN proximity sensors with internal pull up resistor.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 8/18
Fig. 7 Wiring diagram to connect PNP open collector proximity sensors
Connectin PNP open collector proximity sensor with the C11 Rev. 8
Board R Value (12V) R Value (24V)
C11 Rev. 8 470Ω 1KΩ
Table 1. R value to Connect PNP open collector proximity sensor with the C11.
Fig. 8 Wiring diagram to do an “Auto Tool Zero”

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 9/18
4. Special Functions
4.1 Safety Charge Pump “SCHP”. (Pin 17)
This board takes advantage of Mach ability to send a specific frequency through
one of the pins of the parallel port when the program is in control of the system.
CNC machinery can be very dangerous, and you could have a risk of the machine
doing something different that what you intend the machine to do if the program
loses control of your system. Mach be can be programmed in a way, so when it is
“in control”, it delivers a 12.5 KHz signal through one of the pins. This card lets you
use this signal to work as an On/Off switch for your system, enabling a powerful
safety system for your equipment. If you ever had windows crash on you, then this
card is for you. The port can also do weird things while the system is coming up, or
down.
For Configuring the Charge Pump in Mach X:Use the dialog Config / Ports
and pins / Output Signals. Enable the Charge Pump output and configures it as is
shown in the Fig. 8 Next, press the apply button.
Fig. 9. Charge Pump configuration

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 10/18
Selecting the SCHP operation mode.
There is a jumper that allows you
active or deactivate de SCHP.
1-2: SCHP OFF
2-3: SCHP ON
Note: When the Safety Charge Pump is ON and there is a valid signal present, on
the terminal for pin 17, you will get a high. That way you can use that terminal to
enable external devices that need to be on while mach3 is active. These devices
could be: other breakout boards, drivers, VFDs, etc..
6.2 Variable Speed Control. (pin 14)
This function lets you control your spindle with step and direction signals, as if it was
an axis motor. It converts the step signal into an analog (0-10VDC) .
A Variable Frequency Drive or Inverter works by modifying the frequency for AC
motors. You can control most of these devices with an external analog signal (0-
10VDC). That is, if there is 5VDC coming into through the control signal, the motor
will run at 50% of full speed, if there was 10VDC, the motor will run at 100% of full
speed. If there is no signal coming out, then the motor will stop.
This function can also be used on many DC motor controllers by replacing the
potentiometer that controls the speed.
Requirements:
It requires a +12VDC@200mA power supply to operate.
WARNING: To keep the output signals optoisolate , these must not
have common groun or connections to current with other circuits you
are using.
You will require a voltmeter to fine tune your system.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 11/18
Wiring:
Before connecting anything, please be sure to read your VFD’s manual and
make sure you understand all the safety issues.
Please check the wiring guide and wiring samples here:
http://cnc4pc.com/Tech_Docs/C6R5_WG.p f and
http://cnc4pc.com/Tech_Docs/C6R5_WS.p f
Configuring the Control Software:
It is strongly recommend you read your control software’s manual. You need to
configure your control software to control the spindle as if it was an angular axis.
This card requires a 25 KHz input signal in the pin 14 to deliver 10VDC. So you
have to set the speed of the motor (spindle) at maximum. For acceleration values
adjust them to where you feel comfortable. Keep in mind the acceleration of the
motor must also be set in your VFD.
For configuring Mach follow these steps:
1. Go to Config / Ports&Pins / Motor Outputs. Enable the spindle and select the port
and pins you wired for step and direction.
Fig. 10. Ports&Pins configuration screenshot
2. Go to Config / Ports&Pins / Spindle Setup. In the motor control box, check Use
Spindle Motor Output and Step /Dir Motor. Under Pulley Ratios set the pulley
ratios of the machine.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 12/18
Fig. 11. Spindle Setup screenshot.
3. Go to Config / Motor Tuning / Spindle. On Steps per unit put 1,000, set velocity to
maximum. For Acceleration, choose the acceleration that you feel comfortable
with. Start slow, increase acceleration as you test your system. Under Step Pulse
length, use a number from 3 to 5, but start with 3. This number is directly
proportional to the final voltage you will get in the analog output. Use this number
and the fine tuning pot to adjust the voltage you want to get at max speed.
Fig. 12. Motor Tuning and Setup screenshot.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 13/18
After configuring the Mach, these steps should be followed.
Step 1. Ensure that all external power sources are set to OFF.
Step 2. Connect the power supply to the Power Inputs Connectors (X1).
Step 3. Turn on the external supplies
Step 4. Connect a multimeter in the analog outputs connectors (X2) and make and
fine tune this output:
Make sure that when you reach the max
speed in the control software you get 10VDC
out (X2). This voltage can vary depending
on many things, including the electrical
properties of parallel port or breakout board
you are using, the length of the step pulse
your software is delivering, and the normal hi
or low status of your step pin. Play with the
fine tuning pot in the card (X3), the normally
hi or low status of your pin, and the pulse
width.
6.3 Electromechanical relays. (pins 1 and 16)
Mechanical relays are very flexible because they can be used for AC or DC and
come with NO and NC (Normally Open and Normally Closed) positions. Relay are
independents, one reacts to Pin 1 and the other one to Pin16 and that both can be
used at the same time. The relay specification are showed in the below table.
ELECTROMECHANICAL RELAYS SPECIFICACTIONS
Maximun Current (AC) 7A@240VAC; 10A@125VAC
Maximun Current (DC) 15A@524VDC; 10A@28VDC
Table 2. Electromechanical Relays Specifications.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 14/18
6.4 Using the COM configuration jumper.
This is for selecting the value to
get at the COM terminals found
next to step and direction
terminals (Pin2 2-9). Some drivers
expect a ground, and others
expect +5vdc. There is a jumper
that allows you to select +5VDC or
GND for the COM pins.
1-2: COM= +5V
2-3: COM= GND

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 15/18
7. Troubleshooting.
SYMPTOM 1: THE BOARD DOES NOT REACT TO THE SIGNAL.
POSSIBLE CAUSE POSSIBLE SOLUTIONS
-
Pin c
onflict or mach3 configuration
.
It is possible that the port address
used for the pin is not right, or that
there is a pin conflict with the. That is
that you are using that same pin twice.
(it could be assigned to a different
function).
- Go to the device manager in windows,
and check the memory address used for
the parallel port you are using. Usually it
will be 378 for LPT1. Check also that
the port does not have a conflict. Then
in mach3, go to Ports & Pins / Port Setup
and Axis Selection. Check the memory
address is correct.
- Check that the pin you are using is not
been used anywhere else in your setup.
Got to motor output and output signals,
and check all the entries.
-
The board does not like the
waveform it is getting. Some
breakout boards could invert the
signals or modify the pulse width
.
Changing the active low status of the
pin used also inverts the waveform.
- Play with the active low status of the pin
used for the frequency.
-
The signal or
frequencies are
not
getting to the board. It could be the
cable or that you are passing the
signal through the same breakout
board that you are enabling/disabling,
so the outputs could be disabled, so
they will not get to the breakout board.
- Try a different cable.
- Test the pins in the cable (before they
reach the breakout board) with a
multimeter.
-
Problems with Mach3 Pulse
Generation. Mach3 could have
installation problems (you did not
restart immediately after installation),
or there could be something creating a
conflict. Some dongle devices might
cause this, other software, like
QuickTime or drivers for touch screen.
- Test this in a different PC.
- Follow Art’s suggestions for optimizing
up WinXP:
http://www.machsupport.com/downloads
/XP_Optimization.txt.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 16/18
SYMPTOM 2: THE ANALOG OUTPUT DOES NOT REACH THE 10VDC.
POSSIBLE CAUSE POSSIBLE SOLUTIONS
-
Insufficient p
ulse width
.
It is possible
that the signal pulse width is not
enough to activate the optocouplers.
- In Mach X, go to Config / Motor Tuning /
Spindle. Under Step Pulse length
increase this value, use a number from 3
to 5, but start with 3.
-
The signal
is set active low or the
breakout board could be inverting
the signals.
- In Mach X, go to Config / Ports&Pins /
Motor Outputs. Change the active low
status of the pin used for step.
SYMPTOM 3: THE OUTPUTS DO NOT GET ENABLED / NO SIGNALS ARE
COMING OUT.
POSSIBLE CAUSE POSSIBLE SOLUTIONS
-
The EN terminal (Enable Outputs) is
not enabled. The board requires to be
externally enabled.
- Make sure you are providing +5vdc to
the EN terminal. This +5vdc can be
taken from the terminal next to it.
-
The Safety Charge Pump is not
configured. The Safety Charge Pump
can either be configured in the control
software or disabled by moving the
jumper to the disable position.
- Start by disabling the SCHP. Enable it
and configure it once your system is
setup.
SYMPTOM 4: THERE IS NOISE IN THE SYSTEM, OR THE MOTORS DO NOT
MOVE SMOOTHLY.
POSSIBLE CAUSE POSSIBLE SOLUTIONS
-
The board could be underpowered.
- Make sure you are using a +5vdc
1.5amp power supply.
-
There could be a short that could be
draining the power to the board.
- Check that there are no hot spots in the
board or it’s connections.
- Measure the board’s power
consumption, it should be less than
1200mA (depending on the features
used).

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 17/18
SYMPTOM 5: A I/O PIN MIGHT NOT BE WORKING.
POSSIBLE CAUSE POSSIBLE SOLUTIONS
-
A chip may have gone bad.
These
buffers could act as fuses for the
signals, and they can go bad because
of noise spikes or even strong static.
- These chips are inexpensive and readily
available. You can order them here:
http://www.cnc4pc.com/Store/osc/index.
php?cPath=38_43.
- Carefully moving chips around and
checking if the problem moves around
could be a way of figuring out if this is
the case.
-
There coul
d be a problem with the
parallel cable or parallel port.
- Test this with a different PC or parallel
port.
8. Dimensions.
All dimensions are in Millimeters.

C11 (Rev. 8) User Manual
Revision: 02/12/2008 http://cnc4pc.com/TechDocs/C11R8_User_Manual.pdf 18/18
Disclaimer:
Use caution. CNC machines could be dangerous machines. DUNCAN USA, LLC
or Arturo Duncan are not liable for any accidents resulting from the improper use of
these devices. The C11 is not fail-safe device, and it should not be used in life
support systems or in other devices where its failure or possible erratic operation
could cause property damage, bodily injury or loss of life.