ZiLOG Z80-RIO Operating System User's Manual page 38

1
2
reserved
TIB
Bit 6
Bit
7
Local flag
Full/Half duplex
Half=l
Full=O (default)
Holds last character which has
been input from serial
communication port but not yet
transferred by a READ request.
3 Cursor Location
4 reserved
5 •• 138 Tabbing Drum
134 positions used to mark tab
settings (nonzero values)
WRITE STATUS (42H) - Transfers data length bytes
from the data transfer address
to the CON status area
(see above).
DEACTIVATE (44H) - Null operation returns
operation complete
READ ABSOLUTE (46H) - Data length bytes are
received from the console
device. Byte data is ac-
cepted exactly as trans-
mitted. Data length is
unaffected.
WRITE ABSOLUTE (48H) - Data length bytes are sent
to the console device. Byte
data is written exactly as
given. Data length is un-
affected.
All others - returns Invalid request completion code.
During write operations, entering a question mark causes
the operation to pause until a second question mark is
entered. Entering an ESCape always immediately terminates
an I/O request.
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