Serial connection issue with ActiveSync 4.5 and Windows XP

18 May 2007

If you are using Microsoft ActiveSync version 4.5 on a Microsoft Windows XP operating system, you may have difficulty connecting through a serial cable at 115K baud to an Allegro Field PC. Possible solutions and work-arounds are mentioned below.

Alternatives to Serial Cable

If you are using an Allegro CX Field PC or an Allegro CE Field PC, we recommend purchasing a USB/ Power Dock. If you have an older model Allegro Field PC or prefer not to use a USB/Power Dock, some other alternatives to serial cable are mentioned on our website at:

Alternatives to serial cable

Change COM Port

It has been noted that switching to and connecting at 115K baud to the COM2 port on the Allegro, and then switching back to COM1 at 115K baud seems to help with future connections through COM1 at 115K baud to ActiveSync 4.5. To change to the COM2 port:

  1. On the Allegro, tap on the Start button. The other option is to press the Blue and Start keys simultaneously on the keyboard.
  2. Tap on Settings > Control Panel > Communications and/or PC Connection icon/tab.
  3. Tap on the Change button.
  4. Tap on the "Connect to desktop using:" drop-down box, select "COM2 @ 115K baud" or a lower baud rate, and then tap OK.
  5. Confirm the change at the bottom of the PC Connection window, and then tap OK.
  6. Close the Control Panel window and then try the connection again. If you need help connecting, follow the instructions in the Allegro Field PC User Guide. Change back to COM1 if you would like and try connecting at 115K baud.

Change Baud Rate

You can change the serial cable baud rate at which you connect the Allegro Field PC to Microsoft ActiveSync by following these steps:

  1. On the Allegro, tap on the Start button. The other option is to press the Blue and Start keys simultaneously on the keyboard.
  2. Tap on Settings > Control Panel > Communications and/or PC Connection icon/tab.
  3. Tap on the Change button.
  4. Tap on the "Connect to desktop using:" drop-down box, select "COM1 @ 57600 baud" or a lower baud rate, and then tap OK.
  5. Confirm the change at the bottom of the PC Connection window, and then tap OK.
  6. Close the Control Panel window and then try the connection again. If you need help connecting, follow the instructions in the Allegro Field PC User Guide.

Install ActiveSync version 4.2 or 3.8

Uninstalling Microsoft ActiveSync version 4.5 and then installing the older version 4.2 or 3.8 will allow the Allegro Field PC to connect through serial cable at 115K baud.

Follow this link for download links for Windows Mobile Device Center and ActiveSync.