TexLink Interface

 
 
 
  
        
 

TexLink

The TexLink (TXL200/201) interface board provides a fast bi-directional data link between the RAM-SAN and PCI-based computers.  It achieves this by incorporating dual optical links that allow it to transfer data as fast as 200 MB/sec at distances up to 100 meters.  The TexLink resides in one of the RAM-SAN I/O port slots, while its companion interface (PCI200) resides in a host machine in one of its 32/64 bit PCI slots.  Since the RAM-SAN is multi-ported, many computers, workstations, or servers can have their own 200 MB/sec link to the RAM-SAN.  A program running on a host machine accesses the RAM-SAN via TMS library calls. The library calls utilize the PCI interface driver and allows the system to buffer DMAs to and from the RAM-SAN. Additionally, a file system may be mounted to the RAM-SAN to provide transparent access to the RAM-SAN as a Solid State Disk.
 

 
  The TexLink Solution  
The TexLink protocol was created as a means for the user to have a direct high-speed connection to SAM memory.  This was accomplished first by implementing the Fibre Channel protocols FC-0 (media, drivers, and receivers) and FC-1 (8B/10B coding).  Secondly, two optical links were placed in parallel to double the bandwidth achievable with a single link.  Finally, a minimal signaling protocol (command and control) was developed which allows flexibility yet keeps overhead to a minimum.  In addition, the use of Multi-mode fiber allows interconnection distances of up to 100 meters and reduces EMI problems in transmission lines.
 
TexLink Features
The TexLink interface is designed to provide a fast stable interface for high-speed dedicated I/O. The design allows for near fibre speed transfer rates of 200 MB/sec half duplex. The memory structure of the interface is designed to give high-speed, pass-through ability to RAM-SAN memory reducing latency and increasing bandwidth.  And the multi-ported, ultra high bandwidth features of the RAM-SAN allow for several PCI-based computers to have their own independent and concurrent link to the RAM-SAN.