pins which ensure proper positioning and a plastic
hook to ensure locking.
The operator replaces the cartridge as neces
sary to ensure high quality printing. The follow
ing text defines cartridge loading procedures:
1. Turn the device OFF.
2. Position the ribbon between the platen and
the print head mechanism.
NOTE: A segment of the ribbon is exposed
at the head of the cartridge (see
3. Gently draw the cartridge away from the
print mechanism (a segment of tape will be
4. Carefully position the cartridge on the
reference pins and the plastic locking clip.
5. Turn the tension knob on the face of the
cartridge to increase the ribbon tension.
6. Turn the device ON.
The Keyboard Typewrite Console Attachment
consists of a device controller, console adapter,
and a console compatible peripheral. Figure 8-6
LEV E L b MEGi,BUS
1- - - - -...,
' -- _ _ _ _ _ J
I - _ _ _ _
Figure 8-6. Device Interconnection/System
illustrates the structure of the subsystem and its
relationship to the system.
The device controller is a microprogrammed
peripheral controller which attaches to the Level
6 Megabus and is capable of supporting up to 4
devices via a configurable series of adapters.
Device specific functionality is provided by the
adapter and certain device specific firmware in
the device controller.
Level 6 software allows for the transfer and
receipt of data from and to the console through a
series of Input/Output programming commands.
These commands and their associated meanings
are summarized in Table 8-1.
Table 8-1. INPUT/OUTPUT COMMAND SUMMARY
Input Interrupt Control
Input Range (ReSidual)
Input Configuration Word A
Input Configuration Word
Input Status Word
Input Device ID
Input Address (Lower
Input Address (Upper
Input Task Word
Input Attention Character
Output Interrupt Control
Output Address and Range
Output Configuration Word A
Output Configuration Word
*The low order bit of the channel number of this command specifies the direction of the data transfer (i.e., input or output). The low
order bit of the channel number is ignored on all other commands.
KEYBOARD TYPEWRITER CONSOLE