title: Transaction Management eXecutive
text: # Transaction Management eXecutive
  
  Transaction Management eXecutive or TMX was NCR Corporation's proprietary transaction processing system running on NCR Tower 5000-series systems which were based on Motorola 680xx CPUs. This system was used mainly by financial institutions in the 1980s and 1990s.
  
  ## Features
  
  Basic features of the TMX operating system are listed below:
  
  * It was a multiuser, multitasking 32-bit operating system.
  * It featured a proprietary network called LBN (Local Branch Network).
  * Later versions of TMX had Token Ring support which was called LBN Emulation.
  * It had device support for financial applications on LBN, e.g. NCR dumb terminals, passbook printers, cash dispensers, magnetic stripe reader and pinpad.
  * It contained SNA LU emulations for mainframe connectivity.
  * Peripheral device configuration was fixed during boot time. Configuration changes were made using the SYSGEN command.
  * It supported a flat file system; there were no subdirectories. File name format was like this: diskname:usernumber.catalogname.filename.ext;version
  * Files had various types, like text files and index sequential data files.
  * Main programming language was Whitesmiths C, but the compiler was not ANSI C compliant.
  * It had limited memory (several MB) and disk (several hundred MB).
  
  NCR Tower 5000 systems were also capable of running UNIX SVR3 version.
  
  