Instruction Set Descriptions
LANCAM B Family
Instruction: Validity Bit Control (VBC)
Binary Op-Code: 0000 f100 00dd dvvv
An RSC instruction resets the Segment Control register
count values for both the Destination and Source counters
to the original Start limits.
f
Address Field flag
ddd
vvv
Destination of data
Validity setting for Memory location
The Shift instructions shift the designated register one bit
right or left. The right and left limits for shifting are
determined by the CAM/RAM partitioning set in the
The VBC instruction sets the Validity bits at the selected
memory locations to the selected state. This feature can be
used to find all valid entries by using a repetitive sequence
of CMP V through a mask of all 1s followed by a VBC
HM, S. If the VBC target is aaaH, the Address register is
set to “aaaH.” For VBC instructions to or from aaaH or
[AR], the Address register increments or decrements from
that value after the operation completes, as set in the
Control register.
Control register. The Comparand register is
a
barrel-shifter, and for the example of a device set to 64 bits
of CAM executing a Shift Comparand Right instruction,
bit 0 is moved to bit 63, bit 1 is moved to bit 0, and bit 63
is moved to bit 62. For a Shift Comparand Left instruction,
bit 63 is moved to bit 0, bit 0 is moved to bit 1, and bit 62
is moved to bit 63. MR2 acts as a sliding mask, where for
a Shift Right instruction bit 1 is moved to bit 0, while bit 0
“falls off the end,” and bit 63 is replicated to bit 62. For a
Shift Mask Left instruction, bit 0 is replicated to bit 1, bit
62 is moved to bit 63, and bit 63 “falls off the end.” With
shorter width CAM fields, the bit limits on the right or left
move to match the width of CAM field.
Instruction: Compare (CMP)
Binary Op-Code: 0000 0101 0000 0vvv
vvv
Validity condition
A CMP V, S, or R instruction forces a Comparison of
Valid, Skipped, or Random entries against the Comparand
register through a Mask register, if one is selected. During
a CMP E instruction, the compare is only done on the
Validity bits and all data bits are automatically masked.
Instruction: Set Full Flag (SFF)
Binary Op-Code: 0000 0111 0000 0000
The SFF instruction is a special instruction used to force
the Full flag LOW to permit setting the Page Address
register in vertically cascaded systems.
Instruction: Special Instructions
Binary Op-Code: 0000 0110 00dd drrr
Instruction: No Operation (NOP)
ddd
rrr
Target resource
Operation
Binary Op-Code: 0000 0011 0000 0000
The NOP (No-OP) belongs to the MOV instructions,
where a register is moved to itself. No change occurs
within the device. This instruction is useful in unlocking
the daisy chain in Standard mode.
These instructions are a special set for the LANCAM to
accommodate the added features over the MU9C1480.
Two alternate sets of configuration registers can be
selected by using the Select Foreground and Select
Background Registers instructions. These registers are the
Control, Segment Control, Address, Mask Register 1, and
the PS and PD registers.
Rev. 5.1
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MUSIC [ MUSIC SEMICONDUCTORS ]
