TM02 magtape controller

The TM02 magtape formatter is a MASSBUS device controller, used with 1/2" magnetic tape drives; supported drives include the TU16 and TE16 (both at 45 inches per second). It can handle 800 bits/inch (NRZI) and 1600 bits/inch (PE - Phase Encoded).

A TM02 can control up to 8 drives, although the TM02 and drives count as only a single MASSBUS entity. The TM02 controller connects to all the drives over a 'slave bus'; all the drives are identical (unlike in the TM11/TU10 system.

Implementation

The TM02 is implemented as a set of boards, all of which plug into a custom hex-high nine-slot backplane, usually mounted in a special box in the first tape drive rack. The modules include two hex-size boards, seven quad-size modules, and six dual-high modules.

The hex modules are:

• M8909 - MASSBUS Interface
• Bit Fiddler
  • M8906 for use with a PDP-11
  • M8914 for use with a PDP-10

The quad modules are:

• 3 x M8901 - Data Sync (PE)
• M8902 - Tape Control (PE)
• M8903 - Tape Control Common Mode
• M8904 - Tape Control (NRZI)
• M8905 - Maintenance Register

The dual modules are:

• M8907 - Control and Write Drivers
• M8908-YA
• M8908
• 3 x M5903 or M5903-YA

The first three are the drive slave bus interface; the last three are the MASSBUS interface.