FIRMWARE UPDATES
From time to time Nexus Audio will release firmware updates for the MRC-816 Controller and/or touch panels.
Sometimes these updates will be improvements to system functionality and sometimes they will be new feature
additions. Updating firmware on the MRC-816 is done with a USB Flash (thumb) Drive.
Updates can be obtained by contacting Nexus Audio Systems Inc.
The file for the MRC-816 Controller (if included) will be named C816B.Vx_xx.hex where x_xx denotes the version
number. Similarly, the file for the touch panels (if included) will be named NEXUSTP1.bin.
The USB flash drive to be used for the upgrade can have other files on it, but if there are a lot of files, the MRC-
816 may take a long time to initialize before the upgrade begins. If the MRC-816 does not initialize or download
the update, delete the extraneous files, or use another flash drive with less files on it.
Upgrading the MRC-816 Controller
1. Unzip, and copy the file C816B_Vx_xx.hex to a USB flash drive in the root directory. NOTE: only have one
version of the file in the root directory. If there are multiple versions, the correct one may not be loaded. If you
want to keep older versions that may be present on the drive, move them to a sub-directory.
2. Turn off the MRC-816.
3. Insert the USB flash drive into the USB port on the MRC-816 Rear Panel.
4. While holding down the FN button beside the power switch, turn on the MRC-816. Then release FN. The
status led beside the LAN port should start to flash.
5. Wait for programming to complete. The status led will begin to rapidly flash as the new software loads. You
will know when programming is complete, as the status led will stop flashing, and the front panel leds will
begin light up as touch panel scanning commences.
6. Remove the USB flash drive.
7. If using a slave chassis, it will need to be upgraded in the same manner.
Upgrading the MRC-816 Touch Panels
1. Unzip, and copy the file NEXUSTP1.bin to the root folder of a USB flash drive.
2. As a check, turn the MRC-816 OFF, then ON, and verify that all attached touch panels are properly detected
by observing the front panel leds as described in the system power up section. An un-detected touch panel
will not be updated.
3. Insert the USB flash drive containing the update into the USB port on the MRC-816 Rear Panel.
4. In the web end menu, navigate to the USB tab.
5. The status area in the USB menu should say “drive detected”.
6. Click on the “Update Touch Panels” button to begin the update
7. The screens on all touch panels will go blank, and then display the progress of the update.
8. When update is complete, the touch panels will reboot, and the normal screen will display for a few seconds
before the touch panels go to sleep. Sometimes, a touch panel will not reboot, and will be displaying a
message “reboot” now”. If this happens, turn the MRC-816 off, then back on.
RS-232 PROTOCOL
The MRC-816 Controller has an RS-232 Port that allows the system to be controlled with a third party controller to
become a sub-system in a whole-house control package. This allows system operation such as turning on certain
zones for background music when the alarm system is deactivated. Conversely, a command can be sent to turn
all zones off when the alarm system is activated. Many such scenarios are possible.
The MRC-816 RS-232 Port allows full control of all system functions. In addition to being able to control the MRC-
816 Controller’s ‘on board’ functions (ON/OFF, input select, etc) RS-232 control also allows control of the
connected source components. When the MRC-816 ‘sees’ a command for one of the on board functions, it
responds accordingly. When it sees a command such as CD play, the incoming RS-232 command is interpreted in
a similar manner to a touch panel button press and the MRC-816 will then output the appropriate corresponding
IR command.
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