RCA 70/700 Series Reference Manual page 126

Table 3-5 Operational Word 1 (OW-I)
Bit Function
16
(Fetch
OW-2)
17
(Hardware
Parity)
OW-l
1
o
Access (staticize) operational word 2 to
accomplish additional operations.
Operational Word 2 is not being used.
This parity bit is set or reset to maintain
odd parity for this OP WORD by the hardware
upon CCM initialization (the memory loading
of the Op Word) and is checked by hardware upon
each subsequent access of the Op Word.
If a parity error occurs (upon any CCM memory
access), the CCM becomes inoperable and must
be reinitialized to restart operation.
8