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• Once the reprogramming is com-
plete, the m905 RCU will disconnect/
reconnect itself from the computer.
Open the folder again. A file named
“SUCCESS.TXT” should be in the folder.
This is your indication that the firm-
ware update process has completed
successfully.
• If the m905 RCU encounters any
problems during the USB upgrade
process, the folder will contain a file
named “ERROR.TXT”.
• The type of problem encountered is
reported on the Status line in ERROR.
TXT. In this example, a firmware
file for the ACU was accidentally
uploaded as indicated by the “Invalid
Device” error. Should an error occur,
restart the firmware upgrade process.
• Disconnect the USB cable from the
RCU and then cycle the power to the
m905.
UPDATING ACU FIRMWARE
TO UPDATE THE FIRMWARE ON THE m905 ACU PERFORM THE FOLLOWING STEPS:
• Download the m905 firmware package from the Grace Design Website and unzip it on your computer.
• Turn off the m905 and connect your computer via USB to the USB upgrader port on the m905 ACU.
• Turn on the m905. The m905 will enter USB upgrader mode instead of communicating with the m905 RCU.
(the m905 RCU will display a communication error.)
• Once the m905 initializes it will appear
on your computer as a ‘mass storage class’
device with the name m905_ACU.
• Open the folder. It will contain a single
file named “READY.TXT”. This indicates that
m905 ACU is now ready for the firmware
update. Simply locate the firmware file
that was downloaded (filename starts with
m905_ACU), drag and drop the file to the
folder containing READY.TXT.