Texas Instruments TMS320C2XX User Manual
Page 246
Load TREG and Accumulate Previous Product
LTA
7-93
Assembly Language Instructions
Syntax
LTA
dma
Direct addressing
LTA
ind [, ARn]
Indirect addressing
Operands
dma:
7 LSBs of the data-memory address
n:
Value from 0 to 7 designating the next auxiliary register
ind:
Select one of the following seven options:
* *+ *– *0+ *0– *BR0+ *BR0–
LTA
dma
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
1
1
1
0
0
0
0
0
dma
LTA
ind [, ARn]
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
1
1
1
0
0
0
0
1
ARU
N
NAR
Note:
ARU, N, and NAR are defined in Section 6.3,
Indirect Addressing Mode (page 6-9).
Execution
Increment PC, then ...
(data-memory address)
→
TREG
(ACC) + shifted (PREG)
→
ACC
Status Bits
Affected by
Affects
PM and OVM
C and OV
Description
TREG is loaded with the contents of the specified data-memory address. The
contents of the product register, shifted as defined by the PM status bits, are
added to the accumulator, and the result is placed in the accumulator.
The carry bit is set (C = 1) if the result of the addition generates a carry and
is cleared (C = 0) if it does not generate a carry.
The function of the LTA instruction is a subtask of the LTD instruction.
Words
1
Cycles for a Single LTA Instruction
Program
Operand
ROM
DARAM
SARAM
External
DARAM
1
1
1
1+p
SARAM
1
1
1, 2
†
1+p
External
1+d
1+d
1+d
2+d+p
† If the operand and the code are in the same SARAM block
Opcode
Cycles