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control bits when a character is to be transmitted.
If
desired for some applications, two eight-
level characters could be stored in a word as eight-bit characters including the parity and
control bits.
18
13 12
7 6
1
XXXXPXXC XXXXPXXC
c c
18
11 10
3
2 1
Instruction Word Format
There are two main groups of instructions:
a character
a character
a character
data bits (four of the six)
parity bit
data bits (two of the six)
control bit
control information for the
word (or not used)
1.
Those for which the low-order bits specify a memory address, and which may be subject
to address modification.
2.
Those for which the low-order bits contain information to be used by the instruction.
The second group is called "general" instructions and may be recognized by the fact that the
three high-order bits, I (16-18), are all zeros.
(When expressed in octal notation, the general
instructions start with a 0.)
There is one format for the "non-general" instructions and three formats for the "general"
instructions (one for register transfer instructions, one for status line and function driver
instructions, and one for C counter instructions).
@&lr&~~lrc::J ~@------------
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