Control Data Cyber 170 State Hardware Reference Manual page 207

PP Programming
Central Memory Read/Write lnstructions
PP instructions can read and write to central memory either single words or
blocks of words.
PP
Central Memory Read lnstructions (60, 61)
-
Instruction 60 transfers one CM word into five 12-bit PP memory words.
Instruction 61 transfers a block of 1 through 811 CM words into 5 through 4095
12-bit PP words.
It is possible to transfer up to 4096 CM words overwriting PP
memory cyclically; location
0,
however, has special properties. The Central
Read description in chapter 4 has more information on instruction 61.
PP Central Memory Write lnstructions (62, 63)
Instruction 62 transfers five 12-bit PP memory words into 1 CM word.
Instruction 63 transfers 5 through 4095 PP memory words into 1 through 811 CM
words.
It is possible to transfer up to 20 480 PP memory words, repeating
information from PP memory cyclically.