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© Sealevel Systems, Inc. R91001 Manual | SL9211 11/2022
SDCARD Boot Sequence
Upon power up, the Relio R9 follows a specific boot sequence. The initial sequence is “firstboot”. The
firstboot process initializes the low level hardware and is responsible for loading the next sequence called
“eboot”. Eboot provides a configuration menu for setting connection types and start up memory locations.
Connection types include Ethernet and USB. Memory locations include SDCARD and NAND Flash.
Ultimately, eboot attempts to load and execute the OS runtime image based on those configuration
settings.
The Relio R9 development board checks the root directory of the bottom SDCARD for a valid Eboot boot
loader (boot.bin). The file must be named boot.bin and the SDCARD must be formatted as FAT 12/16/32.
If no boot image is found, the device will next check the raw data in the NAND Flash.
Only the bottom SDCARD slot (Slot A) or NAND Flash can be used for booting to an OS runtime
image. .
The Relio R9 ships with an SDCARD loaded with the OS files listed below:
•
Boot.bin
•
Eboot.bin
•
NK.bin
OS File Restoration
In the event that Sealevel produces updated OS file versions, or a backup is desired, the OS files will need
to be copied to the root directory of an SDCARD or programmed to the NAND Flash. There are a variety of
ways to copy files to the SDCARD; please see the section labeled “Upgrading the OS runtime image on
SDCARD” below for more detail. Please see the section labeled “Upgrading the OS runtime image on NAND
Flash” for further detail into that process. The NAND Flash cannot be programmed until any existing OS
runtime image has been removed and the SDCARD is removed or the OS image on it is removed.
Using the Debug Port
This procedure requires an available RS-232 COM port or USB to RS-232 serial port adapter attached to a
host PC, a Relio R9 Serial Debug cable (Item# CA429), and any telnet terminal client application such as
PuTTY (See Appendix A). For this procedure, we will demonstrate the use of PuTTY.
Connect the 4-pin keyed female end of the Relio R9 RS-232 cable into the Relio R9 connector (J6). To access
this connector you will need to remove the cover of the Relio R9 and locate the connector on the exposed
motherboard. Connect the DB9 end of the Relio R9 RS-232 cable into an available serial port on the host
PC.
