88CHAPTER 6: SWITCH MONITORING AND MAINTENANCE
Figure 62 Hyper Terminal serial interface attribute settings
Upgrading software XModem is a file transfer protocol used for its simplicity and performance. It through console port transmits files through serial interfaces, supporting 128 bytes and 1Kbytes in data
(XModem) units, checksum and CRC checking modes, and multiple transmissions attempts (usually 10 attempts) when packet errors are found.
XModem completes the transmission by the receiving program (receiver) and the sending program (sender). In XModem, the transmission begins by sending negotiation characters from the receiver for the purpose of check mode negotiation. After passing the negotiation, the sender is allowed to send the first data packet. Upon receiving the complete packet, the receiver checks the packet using the agreed upon check mode and sends an ACK if the packet has passed the check and a NAK if it did not. After receiving the ACK, the sender sends the next packet; if it receives a NAK, the sender retransmits the previously sent packet.
To run the Xmodem application:
1In the Boot menu, type 4, press Enter, and the system accesses the serial interface submenu as follows:
SERIAL SUBMENU
1.Download file to SDRAM through serial interface and boot
2.Download file to Flash through serial interface
3.Download file to HardDisk through serial interface
4.Modify serial interface boot parameter
0.Return to main menu Enter your
