Replacement PIC chip with latest TCF Firmware (17565-X)

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$ 25.00
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TCF Controller Firmware Update

#17565 - Replacement PIC chip with latest TCF Firmware
The original TCF-S focuser controller circuit includes embedded software or firmware to provide motor control, temperature compensation, and serial communications for an external control PC.  From time to time the TCF firmware has been updated and improved to provide greater reliability and feature enhancements. The firmware can be updated in older TCF controllers by ordering and replacing the programmable PIC microcontroller.  Replacement is easy for most users using simple hand tools.  Because the PIC microcontroller is installed in a socket, no soldering is required.
Original TCF-S with Control Box
In most cases the TCF-S controller display will show the currently installed firmware during boot up and homing.  You can also find the version for your firmware using TCF-S Commander software.  Click Help - About while the TCF-S is on and connected.  Firmware versions developed prior to 2008 may be reported as V.old meaning that version was produced before the serial version query command was implemented. 

There have been several revisions to the TCF-S main control board over the years with the most recent revision 5 boards being produced today.  If the current version is 2.40 or earlier, the board revision is either Rev 3 or Rev 4.  For current firmware versions 4.00 and higher the board would be the current Rev 5.  We recommend all older boards operate at firmware version 2.40 for full compatiblity with the latest TCF-S Commander and ASCOM driver software version 6  

TCF-Si Focuser with Integrated Control Circuit

The TCF-Si focuser with integrated circuit uses a smaller PIC microcontroller which is also socketed for easy replacement.  The firmware version for this series of focusers can be found by clicking Help - About in TCF-S Commander software while the focuser is powered and connected.  Removing the on the control circuit box located on the side of the focuser motor housing will reveal the circuit board.  Each PIC microcontroller chip will also have a labeled identifying the version number.

TCF-Si and TCF-S3i focuser firmware versions began with version 3.00 introduced in August 2009.  The most recent and current firmware version is shown below.

Circuit Board Component Diagram

Refer to Appendix B of the latest TCF-S Technical Manual for a component diagram of each control board revision.

Current Firmware Versions

  • TCF-S and TCF-S3 focusers with Rev 3 or Rev 4 boards:   V2.40
  • TCF-S and TCF-S3 focusers with Rev 5 boards:   V4.11
  • All TCF-Si and TCF-S3i focusers:  V3.12

Note that the TCF-Lynx and TCF-Lynx3 focusers use the FocusLynx controller and can be flash-updated.  For the FocusLynx Hand Controller Upgrade firmware, follow this link.  

#17565-2.40 - TCF-S Rev3/4 Firmware Update 

#17565-4.11 - TCF-S Rev5 Firmware Update

#17565-3.12 - TCF-Si  Firmware Update

The #17565 TCF Firmware Update includes a pre-programmed PIC microcontroller for insertion into a mating socket on the TCF control circuit.

TCF-S Firmware Replacement Instructions:

Download the #17565  TCF Firmware Update instructions in pdf format.

Personal Upgrade Path

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