PM856 Processor Won't Boot from CF Card - Instead Fault (F) LED is Flashing Slowly???
The manual does not describe what a slow flashing Fault LED means on the PM856 processor. I have seen a fast flash before when upgrading firmware & that is what the manuals describe for a flashing Fault LED. However, I have an end-user that says the PM856 will not boot from the CF card, which has previously been formatted and files / folders were downloaded from Compact Control Builder correctly. Instead the Fault LED just slowly flashes. Please help as this is a time sensitive issue....
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This can happen in case the inserted card previously has been used for upgrading firmware.
Even if the card is later formatted in Windows, the first sector on the card may still contain the beginning of the firmware file. The controller will find it at start up and will go into firmware upgrade mode rather than loading the application.
Preferably, use dedicated card for firmware upgrade. Else, use a “disk wipe utility” (goggle on that phrase) to empty the card completely.
Also make sure to format the card in FAT16 when using firmware earlier than 5.1. Support for FAT32 was introduced in version 5.1.
Well, at this point something is broken. Its either a problem with the CPU or a problem with the CF card. You need to isolate where the problem is...
- The controller Boot sequence is independant of the CF card. So does the controller boot without the CF card installed ?
- If the controller boots without the CF card can they load it from Control Builder ? ( if the battery is OK then they should be able to move the controller )
- Can the customer connect the programming cable to port 4 and capture the boot sequence using hyperterm ?
- Does the CF card boot another controller ?
- Has the CF card been proven to work with the currently loaded software or is this a new software load ?
- Hopefully the customer has another CF card with an older working version of the program. Does this work ?