TM 11-6625-3081-23
1-21. ELECTRONIC STATION (cont)
1-21
(c) The parallel data is transferred to the IEEE 488 bus interface where a
status check is performed, the handshake sequence between extenders is performed,
and the data frame is put onto the IEEE 488 bus.
(3) Transmit Mode.
After the receive data frame has been accepted and the
handshake sequence completed, the HP-IB extender assembles a return frame. The
return frame is passed to the 16-bit data register, clocked into the encoder,
encoded into a transmit data frame, and transmitted over coaxial cable by the
transmit driver.
i.
DISC/TAPE DRIVE ASSEMBLY 1A1O
(1) Disc/tape drive assembly 1A1O (Hewlett Packard HP7914R) consists of a
chassis assembly, tape drive assembly, disc drive assembly, power supply assembly,
and CCA card cage.
(2) The disc drive is a medium performance, random access, data storage device
with a formatted storage capacity of 132.1 megabytes.
The disc module includes an
electromagnetic rotary head positioning system, spindle, spindle and blower motor,
air filtration and cooling system, and-associated electronic components.
(3) The power supply is mounted to the rear and contains a transformer, filter
capacitors,
ac input circuitry, fuses, and power regulator.
(4) The cartridge tape unit uses a preformatted data cartridge. Data is loaded
onto the disc drive via the cartridge tape unit.
Also data copies can be made by
loading data from the disc drive onto a cartridge tape.
(5) The CCA card cage is located and accessible from the front of the chassis
assembly.
CCAs are located in slots and provide for tape control, disc control, and
HPIB interface bus.
(6) Internal diagnostics are used to detect and isolate malfunctions within the
disc/tape drive assembly.
These diagnostics are automatically performed during
power-up, while the drive is idle, or when manually initiated. The diagnostic
program is resident in the microprocessor CCA.
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