LIST-XL Family
Instruction Set Descriptions
Instruction: Validity Bit Control (VBC)
Binary Op-Code: 0000 f100 00dd dvvv
Instruction: Special Instructions
Binary Op-Code: 0000 0110 00dd drrr
f
Address Field flag
Destination of data
Validity setting for Memory location
ddd
rrr
Target resource
Operation
ddd
vvv
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
PDregisters.AnRSCinstructionresetstheSegmentControl
register count values for both the Destination and Source
counterstotheoriginalStartlimits.TheShiftinstructionsshift
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 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,
andbit62ismovedtobit63.MR2actsasaslidingmask,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.
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
Addressregisterwillincrementordecrementfromthatvalue
after the operation completes, as set in the Control register.
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.
Notes:
* Instruction cycle lengths given in Table 6 on page 15.
† If f=1, the instruction requires an absolute address to be supplied on the following cycle as Command write. The value
supplied on the second cycle will update the address register. After operations involving M@[AR] or M@aaaH, the
Address register will be incremented or decremented depending on the setting in the Control register.
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Rev. 3.1
MUSIC [ MUSIC SEMICONDUCTORS ]
