Motorola MVME187 User Manual

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Debugger General Information
4
RARP/ARP Protocol Modules
The Reverse Address Resolution Protocol (RARP) basically consists 
of an identity-less node broadcasting a "whoami" packet onto the 
Ethernet, and waiting for an answer. The RARP server fills an 
Ethernet reply packet up with the target's Internet Address and 
sends it. 
The Address Resolution Protocol (ARP) basically provides a 
method of converting protocol addresses (e.g., IP addresses) to 
local area network addresses (e.g., Ethernet addresses). The RARP 
protocol module supports systems which do not support the 
BOOTP protocol. 
BOOTP Protocol Module
The Bootstrap Protocol (BOOTP) basically allows a diskless client 
machine to discover its own IP address, the address of a server host, 
and the name of a file to be loaded into memory and executed. 
TFTP Protocol Module
The Trivial File Transfer Protocol (TFTP) is a simple protocol to 
transfer files. It is implemented on top of the Internet User 
Datagram Protocol (UDP or Datagram) so it may be used to move 
files between machines on different networks implementing UDP. 
The only thing it can do is read and write files from/to a remote 
server. 
Network Boot Control Module
The "control" capability of the Network Boot Control Module is 
needed to tie together all the necessary modules and to sequence 
the booting process. The booting sequence consists of two phases: 
the first phase is labeled "address determination and bootfile 
selection" and the second phase is labeled "file transfer". The first 
phase will utilize the RARP/BOOTP capability and the second 
phase will utilize the TFTP capability.