
Data Device Corporation
62743_pre7_noSA-DB.DOC
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8-07-02
42
The op code parity bit encompasses all sixteen bits of the op code word. This bit
must be programmed for odd parity. If the message sequence control processor
fetches an undefined op code word, an op code word with even parity, or bits 9-5
of an op code word do not have a binary pattern of 01010, the message
sequence control processor will immediately halt the BC’s operation. In addition,
if enabled, a BC TRAP OP CODE interrupt will be issued. Also, if enabled, a
parity error will result in an OP CODE PARITY ERROR interrupt.
Table 53
describes the Condition Codes.