xmodem

Abstract: This article describes the use of Xmomdem File Transfer Protocol programming, the design for the flash memory embedded system with the PC on the Super terminal software between the file transfer function, in the PC without the installation of special communications software, the implementation of the program in the board upgrade, The data in the Board customization and so on, to the site commissioning and maintenance to bring convenience. In addition, this paper also describes the comm

Source: Kermit,xmodem,ymodem,zmodem Transport Protocol SummaryKermit protocolMessage format:1.MARK, starting Mark Start_char, for 0x01 (CTRIL-A);2.LEN, the length of the remainder of the message, the value range 0~94, the maximum length of the message 96, the length does not include newline characters or tabs;3.SEQ, packet number, modulo 64,;4.type,k_state Packet Type D Data message TD valign= "Top" width= "

As one of the main methods of serial data transmission, the XMODEM protocol may only have access to bootloader. The content of this Protocol on the internet is either in English or not detailed. I have studied 1k-xmodem before writing bootloader, and I have made many references. I would like to share with you my understanding of XMODEM! 1. What is the

File Transfer Protocol: File Transfer is the main form of data exchange. To ensure correct identification and transmission of files during file transfer, we need to establish a unified transfer protocol between the two computers. This Protocol includes File identification, transfer start and end times, and error judgment and correction. The transmission protocols under securecrt are ASCII, XMODEM, ymodem, and zmodem4. (1) ASCII: This is the fastest

1. Introduce Xmodem is a widely used asynchronous file transfer Protocol in serial communication, divided into Xmodem (using 128 bytes of data blocks) and 1k-xmodem (using 1024 bytes or 1k bytes of data block) protocol two.This article realizes the 128 byte data Block Xmodem protocol, uses the CRC16 verification, when

1 , connect the switch console port and the computer serial port 1 with the control line, connect with the terminal software with Xmodem function (Win2000 and XP Super terminal will take this function). 2 , set the connection mode for the serial port 1 (if the other serial port is connected to choose another serial port), the rate of 9600, no calibration, no flow control, stop bit 1. Or you can click the default settings. 3 , the connection after the

Using SECURECRT1. Connect the switch console port and the computer serial 1 (depending on the Device manager) with the control line, and connect with the SECURECRT software with Xmodem function;2. Set the connection mode for serial port 1 (if the other serial port is connected to choose another serial port), rate 9600, no calibration, no flow control, stop bit 1 (or restore the default settings)650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M0

1. Connect the switch console port with the computer serial port 1 with the control line, and connect with the Super Terminal software with Xmodem function; 2. Set the connection mode for the serial port 1 (if the connection is another serial port on the selection of other serial port), rate 9600, no check, no flow control, stop bit 1 (or restore default settings) 3. Connect the device, Super Terminal return appears the switch without iOS interface,

This article describes in detail how to restore the IOS of a Cisco router in the ROMMON state and how to use TFTP to restore IOS; use Xmodem to restore IOS. It is a common task for a new user to accidentally delete or upgrade IOS, and enter the ROMMONROMMON status after restarting, the former may be larger. Both of them can enable the router to enter the ROMMON status, and cannot perform normal routing forwarding functions and software configuration.

IOSRecovered2Method If you accidentally delete the Router or Switch IOS, especially if the IOS in Flash and the Mini IOS in ROM are no longer available, what can be done to restore it? There are two methods. Actually, I only know two types :) Method 1: X-Modem I have tried one method before, that is, when Flash is deleted, it cannot be started and can be restored using X-Modem. At that time, I accidentally deleted the Flash ios of a Cisco2950 switch, which caused the system to fail to start. Aft

The RS-232 mode allows simple connections to three lines: Tx, Rx, and ground. However, for data transmission, both parties must use the same baud rate for data at regular intervals. Although this method is sufficient for most applications, the use of this method is limited when the receiver is overloaded. In this case, the serial handshake function is required. In this section we discuss three of the most common RS-232 handshakes: Software handshakes, hardware handshakes, and

TFTPDNLD command.Rommon 9 >tftpdnld (transfer file) appears prompt select Yip_address:10.32.10.1ip_subnet_mask:255.255.255.0default_gateway:10.32.10.32tftp_server:10.32.10.32Tftp_file:c2600-i-mz.122-11.binInvoke This command for disaster recovery only.Warning:all existing data in all partitions on flash'll be lost!wish to continue? y/n: [n]: YReceiving C2600-i-mz.122-11.bin from 10.32.10.3...File reception completed. Copying file C2600-i-mz.122-11.bin to Flash.Erasing Flash at 0x607c0000Ogram F

8 9/ ------- The cross-section of a line that is connected from the computer. Pin function of RS-485 and RS-422 Data: txd+ (pin 8), txd-(pin 9), rxd+ (pin 4), rxd-(pin 5) Handshake: rts+ (pin 3), rts-(pin 7), cts+ (pin 2), cts-(pin 6) Ground: GND (pin 1) 5, what is a handshake. The RS-232 Pass mode allows simple connection of three lines: Tx, RX, and ground. However, for data transmission, both parties must use the same baud rate for the timing of the information. Although this approach i

If you accidentally deleted router or switch iOS, especially in Flash iOS and ROM in the Mini iOS are not, even if the boot is not possible, how to recover it? The answer is that there are more than one method, but two. Actually I only know two kinds:)The first method: X-modemI used to try a method, that is, when Flash is deleted, boot cannot enter the system, you can use X-modem to restore it. I accidentally deleted a Cisco2950 switch flash IOS, causing the system to fail to start, after lookin

first you need to have iOS files, if you do not back up the original file, you can find a version of iOS to replace. The first method: X-modemI used to try a method, that is, when Flash is deleted, boot cannot enter the system, you can use X-modem to restore it. I accidentally deleted a Cisco2950 switch flash IOS, causing the system to fail to start, after looking at a lot of data to get a conclusion: the only way to recover through the x-modem. My recovery method is as follows:1, connect the sw

8), txd-(PIN 9), rxd + (PIN 4), rxd-(pin 5)Handshake: RTS + (Pin 3), RTS-(pin 7), CTS + (PIN 2), CTS-(Pin 6)Ground: Gnd (Pin 1) 5. What is a handshake?The RS-232 mode allows simple connections to three lines: Tx, RX, and ground. However, for data transmission, both parties must use the same baud rate for data at regular intervals. Although this method is sufficient for most applications, the use of this method is limited when the receiver is overloaded. In this case, the serial handshake functi

With the development of China's routing industry, we have also promoted the update and upgrade of the routing switch technology. Here we have introduced the IOS restoration method of the Cisco routing switch, and we have tried one method, after Flash is deleted, the system cannot be started. You can use X-Modem to restore it. At that time, I accidentally deleted the FlashIOS of a Cisco2950Cisco route switch, causing the system to fail to start. After checking a lot of information, I came to the

"File Transfer" to modify the default upload and download paths. To change the background color and file name color of the SecureCRT terminal, click "option"-"session option" on the menu bar ", in the "terminal"-"simulation" category, select "ANSI color" and "select a backup keyboard simulation-Linux" in the right window ". XMODEM is a widely used asynchronous file Transport Protocol for personal computer communications using a dial-up modem. Thi

IOS is the core of a vro switch device, and IOS is internet operate system. It is like a computer's operating system windows. Although it is a software, it cannot run any software if it encounters a problem. Therefore, if there is a problem with IOS, the routing switch device will not be able to run normally, and the configuration commands will all be lost. We can only reinstall IOS. 　　 This document uses cisco 3550 as an example to describe how to restore IOS: 　　 　　 Step 1:Use the control line

Prepare the IOS file of the corresponding model. You can download it from Cisco or export the IOS file of the vswitch or vro. Use the Console line to connect to the Console port of the vswitch or vro and open the CRT for download.) Alternatively, use the Super Terminal at the start of xp-Program-attachment-communication-Super Terminal. 1: The switch is lost. The command line mode entered after IOS is started is Swith: In this case, switch: flash_init should be performed to initialize flash. Swi