3Com 2900 manual Loading Files Using Xmodem Through Console Port, Introduction to Xmodem

5.Modify BootRom password

6.Enter BootRom upgrade menu

7.Skip current system configuration

8.Set BootRom password recovery

9.Set switch startup mode

0. Reboot

Enter your choice(0-9):

The items in the Boot ROM menu are described in Table 4-2

z

z

Currently, Boot ROM files are not provided separately by the 3Com Baseline Switch 2900 Family; instead, they are stored together with application files in the files with the name extension of .bin. The procedures for loading Boot ROM files and application files are similar except that you need to select different items (1 for loading application files, and 6 for loading Boot ROM files) in the Boot ROM menu. This manual takes the loading of Boot ROM files as examples.

Loading Files Using XMODEM Through Console Port

Introduction to XMODEM

XMODEM is a file transfer protocol widely used for its simplicity. XMODEM transfers files through the console port, supporting data packets of 128 bytes. With respect to reliability, it supports checksum, CRC, and the error packet retransmission mechanism. Normally, the maximum number of retransmission attempts is ten.

XMODEM transfer is completed by receiving and sending programs together. Receiving program initiates packet checking method negotiation by sending the negotiation character. If negotiation passes, the sending program starts packet transfer. Upon receipt of a complete packet, the receiving program checks it using the agreed-upon check method. If the check succeeds, the receiving program sends an acknowledgement character; if the check fails, it sends a reject character. Upon receipt of the acknowledgement, the sending program continues to send the next packet; upon receipt of the reject, it retransmits the packet.

Loading a Boot ROM file

Complete the following tasks to load a Boot ROM file using XMODEM through the console port (For details about the HyperTerminal, refer to “Setting Terminal Parameters” on page 4-2):

Task	Remarks
Enter the Boot ROM update menu on the switch	Required
Enter the protocol parameter setting menu	Log in to the switch through the HyperTerminal
	and then configure the protocol used for loading
Configure the switch to download files using
	files.
XMODEM

5-3