dp8344b National Semiconductor Corporation, dp8344b Datasheet - Page 146

• Manufacturer Part Number: dp8344b
• Description: Biphase Communications Processor?bcp
• Manufacturer: National Semiconductor Corporation

6 0 Reference Section
MOVE Move Data Memory
Syntax
MOVE
MOVE
MOVE
Affected Flags
None
Description
Moves a data memory byte into the destination register
specified The data memory source operand may specify
any one of the index register modes mIr
The index register-relative mode
memory address by adding the contents of the index regis-
ter Ir to the unsigned 8-bit value contained in the currently
active accumulator The immediate-relative mode IZ
forms its data memory address by adding the contents of
the index register IZ to the unsigned 8-bit immediate value
n The destination register operand Rd may specify any ac-
tive CPU register where as the destination register operand
rd is limited to the active registers R0 – R15
Example
The first example loads the current accumulator by ‘‘pop-
ping’’ an external data stack which is pointed to by the
index register IX
The second example demonstrates the random access of a
data byte within a logical record contained in memory The
index register IY contains the base address of the logical
record
In the final example the 4th element of an Error Count table
is transmitted to a host The index register IZ points to the
1st entry of the table
MOVE
ADDA
MOVE
EXX
MOVE
mIr Rd
Ir
IZ
a
a
R9 A
0 1
A Rd
n rd
IY
IZ
a
a
a
IX A
3 RTR
A R20
indexed register
register-relative register
immediate-relative limited register
select main A alt B
pop accum from ext stack
calculate offset into record
get data byte from record
transmit 4th element
Ir
(Continued)
a
A
Ir
forms its data
a
A
IZ
a
a
n
n
146
Figure 6-5 4TR
Figure 6-6 4TR
Instruction Format
MOVE
MOVE
T-states
3 4TR
4 4TR
Bus Timing
Operation
MOVE
data memory
MOVE
data memory
MOVE
data memory
MOVE
1
15
1
15
Opcode
1
0
0
0
e
e
Ir
IZ
mIr Rd
Ir
IZ
mIr Rd
a
a
a
0
1
a
0
1
Opcode
A Rd
x
A Rd
x
x
n rd
n rd
11
0
Rd
Rd
rd
e
e
1
0
1
0
0
n
0
6
v
00 IW
01 IX
10 IY
11 IZ
Ir
4
3
Rd
TL F 9336 – 9
rd
0
0