LSI53C825AJ LSI, LSI53C825AJ Datasheet - Page 211

• Manufacturer Part Number: LSI53C825AJ
• Manufacturer: LSI

Specifications of LSI53C825AJ

• Lead Free Status / RoHS Status: Not Compliant

5.5.4 Move To/From SFBR Cycles
Table 5.2
Operator
000
001
1
Opcode 111
Read-Modify-Write
Move data into register.
Syntax: “Move data8 to
RegA”
Shift register one bit to the
left and place the result in
the same register. Syntax:
“Move RegA SHL RegA”
Read/Write Instructions
Subtraction is not available when
used instead of data8 in the instruction syntax. To subtract one value
from another when using SFBR, first XOR the value to subtract
(subtrahend) with 0xFF, and add 1 to the resulting value. This creates the
2’s complement of the subtrahend. The two values are then added to
obtain the difference.
All operations are read-modify-writes. However, two registers are
involved, one of which is always the
Table 5.2
functions of this instruction are:
Read/Write Instructions
Write one byte (value contained within the SCRIPTS instruction) into
any chip register.
Move to/from the
register.
Alter the value of a register with AND, OR, ADD, XOR, SHIFT LEFT,
or SHIFT RIGHT operators.
After moving values to the
compare and jump, call, or similar instructions are used to check the
value.
A Move-to-SFBR followed by a Move-from-SFBR is used to perform
a register-to-register move.
shows the possible read-modify-write operations. The possible
Opcode 110
Move to SFBR
Move data into
Byte Received (SFBR)
register. Syntax: “Move
data8 to SFBR”
Shift register one bit to the
left and place the result in
the
Received (SFBR)
Syntax: “Move RegA SHL
SFBR”
SCSI First Byte Received (SFBR)
SCSI First Byte
SCSI First Byte Received
SCSI First
SCSI First Byte Received (SFBR)
register.
SCSI First Byte Received
Opcode 101
Move from SFBR
Move data into register.
Syntax: “Move data8 to
RegA”
Shift the
Received (SFBR)
one bit to the left and place
the result in the register.
Syntax: “Move SFBR SHL
RegA”
SCSI First Byte
from/to any other
(SFBR), the
register
(SFBR).
5-27
is