Control Data Corporation 6000 Series Reference Manual page 19

EXF CODE WORD
6675 EQUIPMENT
NUMBER
~~~~
1
11 0
I
DESIGNATES DSC
5a
~(WITH
E)(CEPTION OF
STATUS-ALL CODE)
--~~~~~~~......__~~~.......__~~~
FUNCTION)
TABLE 3-4. EXTERNAL FUNCTION CODES
DEFINITION
CODE NOTES
Request Status-all S504 Enables three status-all bits from each of
the four DSC' s.
Request Status S51N Enables a status word (12 bits) from DSC
11
N
11
•
"N" represents the number assigned
to the selected DSC.
Select
S52N Selects DSC
11
N"
Clear
S53N Clears DSC "N"
Select Transmit S54N Selects DSC
11
N" for data transmission
Select Receive S55N
Selects DSC "N" to receive data from the
data set for transfer to the computer.
Clear Interrupt Word
S56N
Clears Interrupt Word Received FF and
Received Status Bit
status bit 2° in controller "N" (interrupt
word= 7622)
*S = Equipment number
Status Response Word
The status response indicates the state or condition of a specific DSC. The computer
{S51N EXF code) must request the status word and designate the respective DSC
(Figure 3-2 and Table 3-5). The 12 lines that carry status information also convey
parallel data to the computer.
3-6
Rev. A