User`s manual

RouterBOARD Crossroads User's Manual
● Connect other peripherals and cables
You can also order a pre-assembled system with RouterBOARD already installed in a case.
Powering
Power options:
● J7 power jack:
11..60V DC (JP2 should be closed)
● IEEE802.3af Power over Ethernet (PoE) on the Ethernet port:
48V DC (JP2 PoE control should be open to comply with standard requirements)
12V DC non-standard PoE powering support (JP2 PoE control should be closed)
RouterBOARD Crossroads is equipped with a reliable 10W onboard power supply that accepts a wide range
of input voltages. The board has a direct-input power jack J7 (5.5mm outside and 2mm inside diameter,
female, pin positive plug) and can as well be powered with PoE. Both power inputs are always active, but
only one should be used at the same time.
Crossroads series boards are compliant with IEEE802.3af Power over Ethernet standard (except power over
datalines) and accept 48V powering over up to 100m (330 ft) long Ethernet cable connected to the Ethernet
port (J5 or J6). The board also accepts non-standard PoE input voltage.
JP2 should only be opened when high-voltage PoE is used. IEEE802.3af PoE controller is only operational
starting from 22-24V DC, so when powering from lower voltage (from either PoE or power jack), make sure
the controller is disabled by shorting the JP2 jumper.
Booting options
First, RouterBOOT loader is started. It displays some useful information on the onboard RS232C
asynchronous serial port, which is set to 115200bit/s, 8 data bits, 1 stop bit, no parity by default. The loader
may be configured to boot the system from the onboard NAND module or from Ethernet network. See the
respective section of this manual for how to configure booting sequence and other boot loader parameters.
Onboard NAND Storage Device
The RouterBOARD may be started from the onboard NAND storage chip. As there is no partition table on the
device, the boot loader assumes the first 4MiB form a YAFFS filesystem, and executes the file called “kernel”
stored in the root directory on that partition. It is possible to partition the rest of the medium by patching
the kernel source.
Booting from network
Network boot works similarly to PXE or EtherBoot protocol, and allows you to boot a Crossroads series
computer from an executable image stored on a TFTP server. It uses BOOTP or DHCP (configurable in boot
loader) protocol to get a valid IP address, and TFTP protocol to download an executable (ELF) kernel image
combined with the initial RAM disk (inserted as an ELF section) to boot from (the server's IP address and the
image name must be sent by the BOOTP/DHCP server).
To boot the RouterBOARD computer from Ethernet network you need the following:
● An ELF kernel image for the loader to boot from (you can embed the kernel parameters and initrd
image as ELF sections called kernparm and initrd respectively)
● A TFTP server which to download the image from
● A BOOTP/DHCP server (may be installed on the same machine as the TFTP server) to give an IP
address, TFTP server address and boot image name
See the RouterBOOT section on how to configure loader to boot from network.
Note that you must connect the RouterBOARD you want to boot, and the BOOTP/DHCP and TFTP servers to
the same broadcast domain (i.e., there must not be any routers between them).
Operating System Support
System Architecture
Crossroads series embedded boards are fully compatible with the standard MIPS32 architecture with PCI
bus.
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