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ChronoFEED SIM Help

Virtual serial ports (com0com)

Three devices connect through a serial port: USB Timing Box, FDS TBox and Microgate REI2. For SIM to emulate them, you need, on the FINISH computer, a pair of virtual serial ports linked to each other: SIM opens one, FINISH opens the other, with its usual driver, which believes it is talking to the real device.

The principle

A serial port links two devices with a cable. To make two programs talk to each other on the same computer, you need two ports and a cable between them: com0com is a free Windows driver that creates a pair of virtual ports; what is written on one is read on the other, as through a crossover cable (the DTR line goes through too: the USB Timing Box needs it for its clock, the TBox to send its times). By default: COM11 for SIM, COM10 for FINISH.

ChronoFEED-SIM
opens COM11 ◀── com0com pair ──▶
(data, DTR → DSR) ChronoFEED-FINISH
opens COM10 (USB Timing Box)
The two ends of the pair, on the same computer.

SIM only opens its port once accepted by FINISH, and closes it as soon as the link drops. A missing or already taken port is reported (once in the log, plainly in the guide) and SIM retries every 5 seconds.

Serial port: installing the com0com virtual ports

Where: com0com ? button; opens by itself once per launch when the SIM port does not exist

Serial port: installing the com0com virtual ports
USB Timing Box connects through a serial port, and ChronoFEED-FINISH connects to it as it would to the real device. For ChronoFEED-SIM and ChronoFEED-FINISH to talk to each other, both must be on the same computer, with a pair of linked virtual serial ports: the free com0com software. To be done only once.
✘ Port COM11 does not exist on this computer (available ports: COM1, COM3). Follow the steps below.1
1. Download com0com 2.2.2.0 (signed version)
https://sourceforge.net/projects/com0com/files/com0com/2.2.2.0/
Take the file "com0com-2.2.2.0-x64-fre-signed.zip" (64-bit Windows; "i386" for an old 32-bit Windows).
2. Install
Unzip the file, then run the installer it contains (right-click → Run as administrator). Accept the driver installation. Keep the default options: a CNCA0 ↔ CNCB0 pair is created.
3. Give the pair COM names
Start menu → com0com → "Setup Command Prompt" (right-click → Run as administrator), then type these two lines:
change CNCA0 PortName=COM10 change CNCB0 PortName=COM11Copy2
Or, in com0com's "Setup" tool: check "use Ports class" for each port and enter the names. If COM10 or COM11 is already taken, choose two other free numbers.
4. Connect both programs
ChronoFEED-SIM: serial port COM11 ("ChronoFEED-SIM serial port" list in the main window). ChronoFEED-FINISH: Timing mode → USB Timing Box, serial port COM10, then switch ON. The two ports of the pair talk to each other; each program takes its own.
If Windows refuses the driver: check in Windows Security → Device security → Core isolation that "Memory integrity" does not block it, or use another virtual serial port program (linked port pair, with the DTR line passed to DSR).
Do not show automatically again ("com0com ?" button to come back here)4Check ports3Close
The com0com help, for a USB Timing Box, before installation.
  1. The status: does the SIM port exist? (green: yes, red: no), and the ports present.
  2. The two commands, ready to copy.
  3. Check ports.
  4. Do not show automatically again.

The texts use the name of the FINISH device and the right ports: the SIM one, and the one FINISH uses if it is known (otherwise the neighbour: COM11 → COM10). The link opens in the browser; if it does not open, it is copied so it can be pasted.

The commands and Copy

Where: step 3

The COMx names are mandatory: com0com names its ports CNCA0 and CNCB0, and neither SIM nor FINISH can open a port named that way. The two lines, already filled in with the right numbers, are typed in “Setup Command Prompt” opened as administrator. Copy puts them on the clipboard.

Check ports

Where: at the bottom

Re-reads the computer's serial ports and updates the status: “✔ Port COM11 exists on this computer (available ports: COM1, COM3, COM10, COM11).”

Do not show automatically again

Where: bottom left

The window no longer opens by itself at launch; it stays available from the com0com ? button. Remembered from one launch to the next.

Installing, step by step

  1. Download

    com0com 2.2.2.0, signed driver version (link in the window), on the FINISH computer.

  2. Install

    As administrator, default options: the CNCA0 ↔ CNCB0 pair is created.

  3. Name the pair

    “Setup Command Prompt” as administrator, then the two commands. One of the two numbers already taken? Take two free numbers, and choose the same one in SIM.

  4. Check

    Check ports: the status turns green.

    In SIM, the Simulated equipment light turns green (“serial port COM11”).

  5. Connect FINISH

    FINISH → Timing mode → the device, serial port COM10 (the other end), then the device switch to ON.

    The FINISH connection light turns green.