General Operation; Netbootloader Interfaces - Kontron PEP CP321 Manual

CP321
5. NetBootLoader
This CP321 board is delivered with the NetBootLoader software already programmed into the
onboard soldered Flash memory. The NetBootLoader itself is a software utility which initializes
the module for operation before turning control over to either an application or to an operator.
This software also provides the capability to monitor and control the operation of the NetBoot-
Loader itself, display system status information, to program executable code and data to the
Flash memory, and to load and start application software.
To attain full operational capability, the NetBootLoader FLASH must be programmed by the
user with application software. Once the application has been programmed to Flash memory,
the NetBootLoader will support the complete boot operation. The following chapters describe
the functioning of the NetBootLoader and how to program the Flash memory.
Note...
The following description assumes a standard CPU board with appropriate
hardware. In the event such hardware is not available, disregard the text that
applies to the missing hardware and proceed as appropriate.
5.1

General Operation

Upon power on or a system reset, the NetBootLoader is started. The CPU board is configured
for operation and control is either passed to an application or an operator. In the event a valid
application has been programmed into the Flash memory and no operator intervention takes
place, the application is copied from FLASH into SDRAM and control is passed to the applica-
tion. If the NetBootLoader does not find a valid application or operator intervention has oc-
curred, control is passed to the operator. The operator now has control to determine the system
status, make configuration changes, read or program the Flash memory, or to restart or shut
down the system.
The operator command interfacing with the NetBootLoader is accomplished either via the
TERM serial port or the Ethernet port. During the boot operation a command interpreter is start-
ed which allows the operator to input commands to the NetBootLoader. Prior to interfacing via
the Ethernet port the network must be configured. This is done via the TERM port.
5.2

NetBootLoader Interfaces

There are four possibilities to interface with the NetBootLoader:
• Via the MC1 (Abort) signal
• Via the TERM serial interface
• Via the SER0 serial interface
• Via the Ethernet interface
Gaining access to the NetBootLoader is a function of the contents of the Flash memory and the
"BootWaitTime" setting. If there is no valid application programmed into the Flash memory, the
boot operation automatically terminates after the module has been initialized and control is
passed to the command interpreter. If there is a valid application in the Flash memory the boot
operation is delayed according to the setting of the boot wait time, and the MC6 (LED1) output
signal is alternately asserted indicating that the boot operation is in a wait state. During this time
the operator may intervene in the boot operation either by asserting the MC1 (Abort) signal,
entering the "abort" command via the TERM interface, or by performing a successful telnet lo-
gin via the Ethernet interface. If the operator does not intervene, the boot operation is continued
after the boot wait time has been exceeded.
ID 24977, Rev. 02 © 2003 Kontron Modular Computers GmbH
NetBootLoader
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