If you need to upload and download files between a Macintosh and an Unisys
A4FX mainframe, consider Avenue Software's Contact product. If the
connection is asynchronous, you only need the software. If not, you will
need their TDI/RS-232 converter, too. Multiple station connectors are
available at a lower cost per workstation price. (Avenue Software
specializes in terminal emulator and data transfer software for
transferring files to/from Unisys mainframes.) For more details, search
the Tech Info Library under "Avenue Software".