John writes:

<<<I seem unable to access the "Enter System Limits" option on my Chelton system. I wonder if my SmartMedia Card, picture attached, got fried somewhere along the way.>>>

The data card is a standard SSFDC (Solid State Floppy Disc Card) that was common in cameras a few years back. It has been tested in sizes ranging from 8Mb to 64Mb. The Ground Maintenance mode is entered when a system is powered up and a SSFDC card is present. Due to a hardware change by the processor module supplier some of the late production (last couple hundred)  IDU-1s (Experimental EFIS Sport) experience a situation where the processor polls the SSFDC controller before the controller is fully initialized. This causes the SSFDC card not to be recognized intermittently.

Inspect the card for damage, dirt or residue. DO NOT attempt to clean the IDU connector with sandpaper!!!! There is a high probability you will snag a contact finger and permanently damage the connector.

Insert the SSFDC with the gold contacts facing down (Experimental IDU-1) or facing up on the certified IDU-III.

Power up the system. If you plan to calibrate the Chelton ADAHRS, Press the button that grounds the ADAHRS Pin 16 while powering on the system (installation specific) to put the ADAHRS in ground mode as well.

If the SSFDC card is not recognized, press the two knobs (left and right) simultaneously for at least three seconds until the screen flashes. This will cause a hot reboot.

If the SSFDC is still not recognized then power down the system and remove it. You should have a PC with a SSFDC reader to allow transferring update information from the PC to the card. Insert the card and see if it is recognized by the PC and if you can read and transfer data onto the card. Transfer some files onto and off of the card to exercise the card's controller. SSFDC's are flash memory devices and flash has a finite read / write cycle life. Sometimes a cell in the file allocation table (FAT) dies and the the card needs to reallocate the FAT cells to recover. Reinstall the SSFDC into the IDU and try again.

If it still doesn't work you can try reformatting the card in the PC (usually doesn't work) or replacing the card. Some camera's have the capability of reformatting the card. The format type is FAT16.

If you cant find a card then contact me by private email.

Regards
Brent Regan