5-3
The loading process of the Boot ROM software is the same as that of the host software, except that
during the Boot ROM loading process, you must enter the different digit after entering the Boot Menu
and the system gives somewhat different prompts. The following text mainly describes the Boot ROM
loading process.
Loading Software Using XMODEM Through Console Port
Introduction to XMODEM
XMODEM is a file transfer protocol that is widely used due to its simplicity and good performance.
XMODEM transfers files via console port. It supports one type of data packets (128 bytes), two check
methods (checksum and CRC), and error packet retransmission mechanism (generally the maximum
number of retransmission attempts is ten).
The XMODEM transmission procedure is completed by the cooperation of a receiving program and a
sending program. The receiving program sends a negotiation packet to negotiate a packet check
method. After the negotiation, the sending program starts to transmit data packets. When receiving a
complete packet, the receiving program checks the packet using the agreed method. If the check
succeeds, the receiving program sends an acknowledgement packet and the sending program
proceeds to send another packet; otherwise, the receiving program sends a negative
acknowledgement packet and the sending program retransmits the packet.
Loading Boot ROM software
Complete the following tasks to update the Boot ROM software using XMODEM through the console
port (For details about the HyperTerminal, refer to
on page
):
Task
Remarks
Enter the Boot ROM update menu on the switch
Configure the switch to download files using
XMODEM
Required
Log in to the switch through the HyperTerminal
and then configure the protocol used for loading
files.
Set the download rate of the console port on the
switch
Required
Log in to the switch through the HyperTerminal
and then set the download rate of the console port
on the switch.
Change the rate of the serial port on the
terminal
Optional
Set the baud rate of the serial port on the terminal
to be consistent with that of the console port on
the switch.
Required
Transmit a file from the terminal to the switch, and
update the Boot ROM file on the switch.
Restore the download rate to the default
Optional
Set the baud rate of the serial port on the terminal
to be consistent with the default rate of the
console port on the switch.
