Release notes - H3C SecBladeII-CMW520-F3169P07

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Introduction to Xmodem
You need to use the Xmodem protocol when upgrading the BootWare program and applications
through the serial interface (console interface).
XModem is a file transfer protocol widely used for its simplicity and good performance. Modem
transfers files through serial interfaces. It supports transmission of packets in 128 bytes and 1024
bytes, error check (checksum and CRC), and error retransmission (generally the maximum number of
retransmission attempts is 10).
XModem transmission is completed by the cooperation of a receiver and a sender. The receiver
sends a negotiation message to the sender to negotiate an error check method. After the negotiation,
the sender starts to transmit data packets. After a complete packet is received, the receiver checks
the packet using the agreed method.
l If the check is passed, the receiver sends an acknowledgement message to the sender. Upon
receiving the message, the sender continues to send the next packet.
l If the check fails, the receiver sends a negative acknowledgement message to the sender. Upon
receiving the message, the sender retransmits the packet.
Modifying Serial Interface Parameters
In practice, on the one hand, you need to improve the baud rate of the serial interface to save the
upgrade time, and on the other hand, you need to lower it to guarantee the transmission reliability.
This section introduces how to modify the baud rate of the serial interface.
Step1 Select 2 on the main menu to enter the serial submenu.
Step2 Select 5 on the serial submenu to enter the baud rate setting menu as follows:
========================<BAUDRATE SET>=======================
|Note:'*'indicates the current baudrate |
| Change The HyperTerminal's Baudrate Accordingly |
| Press 'Enter' to exit with things untouched. |
|--------------------<Baudrate Avaliable>-------------------|
| <1> 9600(Default) * |
| <2> 19200 |
| <3> 38400 |
| <4> 57600 |
| <5> 115200 |
| <0> Exit |
=============================================================
Enter Your Choice(0-5):
Step3 Select a proper baud rate, 5 for example for the baud rate of 115200 bps. The following information is
displayed:
Baudrate has been changed to 115200 bps.
Please change the terminal's baudrate to 115200 bps, press ENTER when ready.
At this time, the baud rate of the serial interface on the SecBlade card is modified to 115200 bps,
while that of the HyperTerminal is still 9600 bps. Therefore, the SecBlade card and the HyperTerminal
cannot communicate with each other. You need to change the baud rate on the HyperTerminal and