Installation Manual
H3C S9500 Series Routing Switches
Chapter 5 Switch Monitoring and Maintenance
5-17
in terms of data unit, checksum and CRC in terms of checking mode, and multiple
retransmissions (usually ten attempts) in the event that packet errors are found.
XModem completes transmission by the receiving program (receiver) and the sending
program (sender). In XModem, the transmission begins with the sending of 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 the receipt of
the complete packet, the receiver checks the packet using the agreed checking mode
and will send an ACK if the packet has passed the check and a NAK if not. Receiving
the ACK, the sender will send the next packet; receiving the NAK instead, the sender
will retransmit the previously sent packet.
z
Xmodem application
1) In the Boot menu, enter
4
, press
Enter
, and the system will access the serial
interface submenu:
SERIAL SUBMENU
1. Download file to SDRAM through serial interface and boot
2. Download file to Flash through serial interface
3. Download file to CF card through serial interface
4. Modify serial interface boot parameter
0. Return to main menu
Enter your choice(0-4):4
2) Enter
4
in the serial interface submenu and press
Enter
to access the following
interface for setting the parameters of the downloading serial interface:
1: 9600(default)
2: 19200
3: 38400
4: 57600
5: 115200
0: Return to serial submenu
please select an appropriate baudrate:
Enter your choice(1-5): 5
3) Select the appropriate downloading speed as needed. For example, enter
5
to
select the downloading speed of 115200 bps, press
Enter
, and the system will
display the following information in the terminal:
BaudRate is 115200 bps. Please change the terminal's speed to 115200 bps
4) At the prompt displayed in the last step, change the baud rate on the Console
terminal to the same one selected for software downloading, disconnect the
terminal and connect it again, press
Enter
, and the terminal will access the serial
interface submenu again:
SERIAL SUBMENU
1. Download file to SDRAM through serial interface and boot
2. Download file to Flash through serial interface
3. Download file to CF card through serial interface