RCA 301, Programmer'S Reference Manual

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H S ector Write Disc Normal (SWN)
General Description
This instruction writes from a selected HSM location to designated sectors of the Data Disc File. From one to
ten sectors of information may be transferred to the Data Disc File with one instruction. 160 characters are transferred
for each sector written.
Format
Operation — FI
N
— Specifies additional number of sectors to be written.
Additional Sectors
0 1 2 3
4
5
6 7 8 9
First File
0
1 2
3
4 5
6 7 8 9
Second File
& A
B C D E
F G H I
A Address — HSM address of the first character to be written. This address must be an even number (left-hand-
end of a diad).
B Address — B
0
— designates the first sector to be written:
First Sector to be Written 0
1 2
3
4 5
6 7 8 9
Will Not O verride Any DDF
Simultaneous Instruction
0 1 2
3
4
5
6 7 8 9
Will Ov erride Any DDF
Simultaneous Instruction
& A
B C D E
F G H I
Bj, B
2
, B
3
— specify zone to which data is to be written:
Module
1
2
3
4
Direction of Operation
Left to right in HSM.
Zone
000 to 107
108 to 215
216 to 323
324 to 431
Outline of Operation
The contents of the HSM diad specified by the A Address are transferred to the Data Disc File Buffer and from
the buffer to the specified sector. The contents of the A Register are incremented by two, and the contents of the
next diad are then transferred. When the additional number of sectors has been written, according to the N character
the operation terminates.
If this instruction contains a bit in the B
0
2*
position and the selected Data Disc File is busy in the Simultaneous
Mode, the Simultaneous Instruction being performed will be terminated on the next transfer of data to or from the
file. The new instruction will then be executed in the normal manner.
Final Register Contents
(A)
f
= Address of HSM location one to the right of the last character written.
(B)
{
= (B)
t
XII-8