GTOCP4 Control Box for Servo Drive
GTO mounts produced since 1998 can be easily upgraded!!!
- All new, completely redesigned with modern chip technology resulting in faster processing speed and increased memory capacity for future feature additions. GTOCP4 supports floating point operands to improve calculation accuracy and coordinate conversions.
- Direct download of future firmware updates for the GTOCP4 (very quick and easy)
as well as the Keypad.
- USB 2.0.
Ruggedized version is rated for very warm
and cold temperatures and is dust tight and water resistant.
- Ethernet can be point-to-point w/PC or networked without
user configuration. Simply enter the IP address into the browser URL and
gain access to the GTOCP4 Web interface. This will provide easy configuration
of your Ethernet and WiFi connections and upload of firmware updates. Additionally,
since the Web interface is built into the GTOCP4, you can access it on
any operating system that supports a Web browser without having to install
any special software.
If you plan to use the Ethernet connection you have several options:
Astro-Physics APCC Standard
and Pro version software. The new version (1.5
or later) has built-in Ethernet support. Connect APCC directly and then
use its built-in virtual serial ports for other software. The AP V2 ASCOM
driver will continue to be connected through APCC's virtual ports. Please
refer to the information below regarding our special APCC pricing.
- Eltima Serial to Ethernet Connector. We do not recommend this option since it does not work for everyone and we cannot support it.
- COM2TCP from AstroGeeks. Note that this emulation software does not presently function with the GTOCP4.
- ASCOM driver. We have plans to add Ethernet support to the ASCOM
driver later this year.
- WiFi to enable connection of your mobile devices or PC
to control your mount. Can be point-to-point for field use, or connected to
a WiFi network. Specify your preference and turn the options on or off within the GTOCP4 browser interface.
- RS-232 ports. We retained both RS-232 ports for those accustomed
to this dependable mode of operation. Note that the lower port
is now fully functional.
- Integrates all functions of the Absolute
Encocders and the Precision Encoders and mechanical Limit Switches. .
Secondary boxes are not utilized. This results in faster response rate
- Applies Safety Slew logic to all slew commands regardless
of source - Keypad or any computer program. This ensures that your mount
will slew safely from a counterweight up position or into a counterweight
up position while using the meridian delay feature.
- 12V - 24V DC power. Servo control system operates from
a readily available 12 volt source, so it
can run for long periods in the field. Compatible with standard automotive or marine batteries. You will need to purchase a Powerpole Cable designed for this control box.
- Backward Compatibility. All of this in a compact size that fits all previous
GTO mounts. Adapters may be required.
Includes features from the lastest version of the GTOCP3
that you rely on.
Features That are NOT Included That We Hope You Don't Miss.
- Allows use of APCC software. The Astro-Physics Command Center (APCC) requires either the CP4 control box or the CP3 control box with the V2 chip installed.
- Allows Automatic "Deadman Switch" Safety Timer function. This
feature confirms that mount
is communicating with the PC and COMs are functioning properly. If
not, the mount will park at the end of a user-defined countdown
preventing pier crash. This important safety feature is implemented
in both APCC Standard and Pro Versions.
- Reads capability of PEM state, guide, center
and slew rates and of drift (both axes) and trim (both axes). This
feature is implemented through polled status command in the ASCOM
V2 driver and APCC Standard and Pro Versions..
- Allows Auto-Park. This will cause the mount to enter
a parked state whenever power is removed and this state is remembered
through power cycles. When the command is invoked, default sidereal
rotation will NOT start up the moment that power is applied. This will
be the recommended setting for any remote observer/imagers. This
does NOT try to move the mount into a pre-defined park position.It
simply puts it into a parked state when power is removed. This feature
is the default in APCC Standard and Pro Versions..
- Improved Meridian Delay logic. The new logic is more
streamlined and robust. It is applied to all go-to slew input - Keypad
and computer programs.
- Accepts timed guide move command. This allows control
programs to introduce precise motion without the complication of providing
accurate time separation between the move and quit commands. Using
your guiding software through the ASCOM AP V2 driver takes full advantage
of this feature.
- Allows variable tracking rate commands in both
RA and Dec axes. These
are useful for tracking objects that are not fixed relative to background
stars, like comets, asteroids, satellites and the Moon.
- Accepts variable centering rate commands. In addition
to the commanded rates of 0.25x, 0.5x, 1x, 12x and 64x. Variable rate
commands are available in the APCC Standard and Pro Versions.
- PEM - Periodic Error Memory correction. Make your
correction just once, remains in memory permanently.
- PEM memory command. PEM memory is accessible to external software
programs in order to smooth out and modify
the curve. PEMPro
by Ray Gralak and distributed by CCDWare supports
directly reading from/writing to the PE storage
locations. This allows more accurate programming
of the mount's PEM (that is, the mount does
not have to interpret move or autoguider commands).
Also, programming is significantly quicker
than waiting for one worm cycle's worth of
playback (5.6 to 7.5 min, depending on the mount model) as is the
case for the GTOCP2. Also, PEMPro reads parameters
and calculates the mount's worm period (useful
if you have a non-Astro-Physics mount with
the GTO Control System.
- High-precision mode. Assures accuracy of R.A. format to
tenths of seconds in R.A. (1.5 arc seconds)
- Alt-Azimuth coordinates. Servo control can be commanded
using Alt-Azimuth coordinates. Utilized by the Keypad, APCC Standard
and Pro and through our ASCOM V2 driver if the software sends alt-az
- Park command de-energizes motor and remembers R.A./Dec.
coordinates when power is removed. Restores saved R.A./Dec. coordinates on next power up and calibrates to them when commanded. When the power and keypad are restored, the mount
will stay parked and not resume tracking until the Resume from Park function
has been entered on the keypad.
- Recalibration. Allows recalibration even when scope has crossed the meridian
and is on the wrong side of the mount.
- Motor stall protection. If motor stalls more than 1 second, the drive will
shut off. This is a safety feature to prevent motor burnout in case
of severe load on the motor due to an extreme imbalance condition or
if the power to the mount has been accidentally left on and the scope
has hit a hard stop.
- Automatic meridian swapping in GoTo slewing mode.
- Continues to track at sidereal rate, even while
slewing. Assures position is always accurate.
- Allows E-W reversal in R.A. and N-S reversal in
declination. For correct object orientation and movement
- Provides full functionality of the AP V2 ASCOM Driver and APCC. Provides
all the commands required for all functions of the AP
V2 ASCOM driver (available free of charge) and our Astro-Physics
Command Center (APCC) software (optional purchase).
- Connections: Reticle, Focus and 6V Auxilliary Power. These are not
widely used any longer.
- Does not have R.A. and Declination backlash control. This was initially
designed for manual guiding.
|Comparison of Control Box Features
- Machined aluminum housing provides robust protection for electronics
- All input lines are protected against heavy static discharge with
- Dovetail construction allows quick removal from all GTO mounts
- 12V DC receptacle (2-pin male) for locking power cable. All upgrades
from previous GTO control boxes will require a new cable
- USB 2.0, ruggedized version for extended temperature range, dusttight
and water resistant
- Ethernet receptacle
- Motor cable receptacle (10-pin female). All motor cables used with GTOCP2 or GTOCP3 will plug in here
- Encoder receptacle (10-pin male). For Absolute Encoder or Precision Encoder
- Autoguider receptacle for any CCD with modular RJ-11-6 connector
- Two 9-pin RS-232 serial ports (DB9 female receptacles, a.k.a. DE9).
If you use APCC Standard or Pro and your computer connectivity is flakey, you can use one of these RS-232 ports as a backup to your USB or Ethernet connections.
If the signal is dropped through your primary input, the serial cable will fill in.
Both ports are full speed.
- GTO Keypad Controller locking receptacle (5-pin female)
- AUX receptacle (7-pin female) for Limit Switches and future planned
functions under development
- Wi-Fi antenna with adjustable postion
|Dimensions of servo box
||6.3" x 4.9"
x 1.5" (16 x 12.5 x 3.8cm)
||1.8 lbs. (0.82 kg)
|Suggested power sources
||Portable 12V battery pack, deep-cycle or marine battery
110 to nominal 12V DC Power Supply (5 amp minimum, regulated and well-filtered
to prevent spikes), like our 13.8-volt,
5-amp power supply (PS138V5AC) .
For the 1600GTO and 1200GTO mounts with a heavy load in colder climates
and for the 3600GTO, we recommend the 15-volt,
12-amp power supply (PS15V12AC)
||Meets FCC and CE standards; Lead-free electronics
Control Options for your GTOCP4
The command language protocol that is programmed into
the microcontroller of the GTOCP4 Control box allows the sophisticated
control functions of your mount. Please keep in mind that the software
that communicates with the mount will determine which commands are utilized.
For instance, although the control box is programmed to include a command
that can implement a timed guide move, if the software
does not issue the command, this feature cannot be used.
For optimum utilization of the advanced functions in
the command language protocol, we recommend that you control your mount
with either software that utilizes the ASCOM V2 driver
or the Astro-Physics
Command Center (APCC). All of
these control options were written by Astro-Physics. For more information,
Your GTO Mounts with Your Keypad, Computer or Mobile Smart Devices.
How Will the CP4 Attach to My
The good news is that all GTO mounts that we have produced since 1998
can upgrade to the new GTOCP4!! Check this link to see what you need
to do to upgrade and if any additional parts are needed: Upgrade
to GTOCP4 Control Box.
Price and Delivery Information
We are presently shipping GTOCP4 Control Boxes. Delivery of your order
will depend on when it was/is placed.
Retail Price: $1,195
NOTE: In order to take full advantage of your GTOCP4, we are offering a 30%
discount on our Astro-Physics Command Center (APCC) Standard and Pro versions when purchased within 45 days of when your GTOCP4 or new mount with GTOCP4 are shipped from Astro-Physics.
Who do you order from? All orders for
the GTOCP4 Control Box must be placed directly with Astro-Physics,
except for customers who ordered their mount from one of our international
1. Read the GTOCP4 Upgrade
and Installation Guide (PDF
document) in order to learn how the CP4 will attach to the mount that you already own and which parts you will need to order.
2. Prepare the required information: Each control box must
be configured for the specific mount based on the characteristics (also
refered to as "personality") of that mount.
Please be prepared to provide the information when you place your order.
You do not have to send the form, we can complete it with information provided
on the phone.
GTOCP4 Order Form (PDF format)
3.Order the parts that you need. Links
and information regarding various components are provided at this
link. Remember that all GTOCP4 control boxes will require a new
power cable since the connector is different than previous control boxes.
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Inc. - All Rights Reserved
This page was last modified:
January 23, 2017
11250 Forest Hills Road, Machesney Park, IL 61115, U.S.A.
Phone: 815-282-1513 Fax: 815-282-9847