Tac32Plus Download Page


The CNS Clock II		Tac32Plus
Totally Accurate Clock plus the Time Interval Counter Module (TIC)
Tac32Plus Software

Software:

Install Tac32Plus for Windows: Download the Tac32Plus installation file by clicking the icon to the left.
USB Drivers for the CNS Clock II: Version 2.12.28 (30-Aug-2017).
Un-compress this library file to a temporary location and use one of the newly created directories to load the USB driver when Windows detects new hardware or use with the update driver function to change to the latest USB driver. The directory “USB Driver” supports 32-bit and 64-bit versions of Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2, Windows 10 and Windows 11. The directory “USB Driver Old – Win 98 and ME” supports Windows 98 and Windows ME.
GPSTime for Windows:  GPSTime is a replacement for Tac32Plus. It is written using the Qt development environment so as to be able to be fielded on multiple operating systems. GPSTime is currently only available as a 64-bit application and has only been tested on Window 10/11 and Ubuntu 22.04.3 LTS Linux. This is the Windows version. The passcode is the same as the current version of Tac32Plus. Please try it out and report your experiences to Rick at CNS Systems, Inc.

Version 1.2.9, November 16, 2025
– Correct the processing of button groups in the GPS Receiver Serial Port Settings dialog box.
– Correct the processing of button groups in the TIC Serial Port Settings dialog box.
– Correct the signal strength calculation for the unusual case where an SSR receiver is emulating a 6 or 8-channel receiver but is sending 12-channel @@Ha messages.
– Improve the handling and reporting of PPS signals.
– Now compiles on QT 6.10.0 with the llvm_mingw 64-bit compiler.
Version 1.2.8, September 28, 2025
– Correct the @@Ca message format in the raw data window and in logs. Previously reported itself as a “@@Fa” message, which was incorrect.
– Add a clear screen button to GPS raw and ID screens and to TIC raw and processed screens. Also start with a clear screen on all but the ID screen.
– Split the GPS Receiver ID screen so the receiver ID data is never erased unless the receiver is reinitialized.
– Eliminate the @@Eq message from the Rx ID screen as it is not relevant there and can fill the screen unnecessarily if active.
Version 1.2.7, August 18, 2025
– Save the state of the GPS Log parameters UseGpsSecondNumber and GpsLogAutorestart so they are available for use when needed and are remembered on program restart.
– Change the calculation of the day of the year for TIC and GPS log file names from PC time to UTC (GPS) time so that logs restart correctly at midnight UTC.
Version 1.2.6, July 30, 2025
– Remove “– PPS –” from GPS PVT logs. This PPS placeholder is useful in the GPS Raw Data screen and raw logs, but in the PVT logs it makes it hard to evaluate log data with a spread sheet program.
– Enable TIC log restart at midnight with a fresh file every day, as is done in Tac32Plus.
– Recalculate 30-day registration timeout at midnight every day.
– For GPS logs, implement auto restart every day, like for TIC logs. Eliminate second offset choices.
– Corrected the date/time format in GPS NMEA logs.
– Corrected the date field in GPS PVT Data Logs when decoding the 8-channel @@Ea message.
– Activate the GPS raw data format log.
– Allow @@Sc in the raw data dialog for receivers that otherwise do not allow other @@S series commands. This is to support advanced features in the SSR series receivers in emulation modes.
Version 1.2.5, July 24, 2025
– Corrected the calculation of signal strength (Eb/No) for six and eight channel receivers. Validated the corrections against an original Motorola VP receiver.
– Add a default data rate of 9600 baud in GpsPortDialog::SetBaud to prevent any possible corruption of the data rate information.
Version 1.2.4, July 22, 2025
– Additional correction to the manual command dialog so that it operates correctly after being opened, closed and reopened.
Version 1.2.3, July 21, 2025
– Corrected the Manual Commands so that when Send is selected the command is correctly sent to the GPS module.
Version 1.2.2, July 9, 2025
– Corrected the processing and display of velocity data for @@Bk and @@Ek messages.
Version 1.2.1, June 29, 2025
– Update to match Tac32Plus Version 2.7.38
– Correct the parsing of model numbers in the @@Cj message.
– Now compiles on QT 6.9.1 with the llvm_mingw 64-bit compiler.
Install GPSTime for Linux: 
GPSTime software for Linux has been developed and tested on Ubuntu Desktop 22.04.3 LTS using the Wayland windows manager (not X11). The distribution file is in deb format that is designed for Debian Linux and its derivatives such as Ubuntu. This release may work on other such releases, but it has not yet been tested. If you test this release, please let us know. Constructive comments are encouraged.

Version 1.1.1 (18-Sep-2023).
– Update to match Tac32Plus Version 2.7.34

To install, download this DEB installation file by clicking the icon to the left. Change to your local download directory and see that the file is present there. Then check the file integrity with this command: dpkg -c GPSTime-1.1.1-Linux.deb. If all is good, install with this command: sudo dpkg -i GPSTime-1.1.1-Linux.deb. GPSTime will be installed in the /opt systems directory that is reserved for the installation of add-on application software packages. To remove GPSTime enter the command sudo dpkg -r GPSTime.

For Linux users, be sure the current user is a member of the “dialout” group. This is needed to give access to the serial ports. The easy way to do this is with the following command issued by a user with administration privileges: sudo usermod -a -G dialout USERNAME

To run the program, click on the GPSTime icon in the applications screen. To run from the command line enter dpkg /opt/GPSTime/bin/GPSTime. The first action is to enter the passcode in the about window and to select the correct serial port in the GPS Receiver Serial Port Settings dialog that is accessed from the menu item Edit / Select GPS Interface.
TCPIP Discoverer: This utility can help find a CNS Clock II when you don’t know its current IP address. It listens to port 30303 for an information packet containing the CNS Clock II’s current hostname, MAC and IP addresses. Just run the executable “tcpip_discoverer.jar” and you will see a windows screen. Press the “Discover Devices” button to solicit a response from the CNS Clock II. Otherwise you will see an unsolicited response on power up or on configuration change.

Documents:


The Documentation for Tac32Plus and the CNS Clock II is available in Adobe format. To download right click on the button to the left and choose to save the target as a file.
The Documentation for Tac32Plus and the original CNS Clock is available in Adobe format. To download right click on the button to the left and choose to save the target as a file.

The TIC Documentation for Tac32Plus is available in Adobe format. To download right click on the button to the left and choose to save the target as a file.
The documentation files require Adobe Acrobat reader.

Tac32Plus Revisions

Latest
Version:
2.7.38		Version 2.7.38, Jun 29, 2025

Corrections:
  • For 53220A and 53230A time interval counters, change the command “SYST:COMM:TCP:CONT?” to “SYST:COMM:LAN:CONT?”. While these commands produce similar results, the LAN command is the only one shown in the counter’s manual.

  • For 53220A and 53230A time interval counters, change the commands INP1:NREJ and INP2:NREJ from ON to OFF. This is based on a warning in the “Keysight 53220A/53230A User’s Guide” 9018-03351.pdf, section “Noise rejection (hysteresis)”, paragraph “Time interval errors”.

  • For 53220A and 53230A time interval counters, it is recommended that users consider manually setting the “User-defined power-on states” to enable recall at power-on based on a state saved after Tac32Plus initializes the counter. Based on field experience, it is not recommended to use “automatic recall” but rather use recall of a specific saved state. Tac32Plus could set this up but it is not clear that all users would want Tac32Plus to make changes to the counter’s state memories.
Version:
2.7.37		Version 2.7.37, April 28, 2025

New Features:
  • Improved the automatic setup for the 53220A and 53230A time interval counters.
  • Support TIC log file names with long name prefixes instead of just four characters. This provides more flexibility in identifying TIC sources such as having two masers with 324KK and 321KK for the filename prefixes. There is no longer a limit to the size of the prefix so you could enter “The_Maser_in_the_Blue_Room_” as a prefix.
  • Support GPS modules with up to 12 digit serial numbers.
  • Recognize the new “++” class of Synergy GPS modules. These have a microprocessor with 256K of program memory.
Version:
2.7.36		Version 2.7.36, March 18, 2024

New Features:
  • Added support for decoding the @@Eq message.
  • For NMEA messages that are not decoded, allow printing in the raw data window and logging so all NMEA messages can be viewed.
Version:
2.7.35		Version 2.7.35, January 8, 2024

New Features:
  • Added decoding for @@Co messages.
  • Added support for 6-channel VP receivers.
Version:
2.7.34		Version 2.7.34, September 18, 2023

Corrections:
  • Correct the parsing of model numbers in the @@Cj message.
  • Change web and email addresses.
Version:
2.7.33		Version 2.7.33, May 27, 2023

Corrections:
  • Bug fixes, improved stability and efficiency.
Version:
2.7.32		Version 2.7.32, October 31, 2022

Corrections:
  • Correct the identification of GPS module firmware version numbers. The SSR series GPS modules changed the way they report this information starting with SSR firmware version 3.55. Incorrect version number identification effects certain internal features like whether to activate the short PPS feature for some receivers.
Version:
2.7.31		Version 2.7.31, July 04, 2022

New Features:
  • Implement support for the new @@SP "Second PPS Rate" command and response. This sets the secondary PPS to frequencies between 1Hz and 1MHz for SSR-128 receivers that support this feature (some hardware with firmware version 3.55 and above).
Corrections:
  • When using the @@Sc manual command, make the Satellite Selection part of the GPS Mode Selection window and the saved data track any changes.
Version:
2.7.30		Version 2.7.30, September 27, 2020

Corrections:
  • When in UBX binary mode, correct the mode settings and transitions between Navigation, Position Hold (0D) and Survey. Note that when terminating a survey early, the mode will return to position hold before it can be set to navigation, regardless of the command settings.
Version:
2.7.29		Version 2.7.29, July 22, 2020

Corrections:
  • Correct the calculations used to resolve the automatic sawtooth correction add vs. subtract determination.
  • Code cleanup – Eliminate unused variables.
Version:
2.7.28		Version 2.7.28, February 11, 2020

Corrections:
  • Improve the decoding of @@Bn and @@En messages.
Versions
2.0 ‑ 2.7.3
1.0 ‑ 1.2.8		For earlier release notes click on the Version 1 or 2 links on the left.