dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 649

• Manufacturer Part Number: dsp56800e
• Description: 16-bit Digital Signal Controller Core
• Manufacturer: Freescale Semiconductor, Inc

TSTA.B
Operation:
S – 0
Description: Compare the low-order 8 bits of an AGU address register with zero, and set the condition codes ac-
Example:
Explanation of Example:
Condition Codes Affected:
Instruction Fields:
Instruction Opcodes:
Timing:
Memory:
Freescale Semiconductor
TSTA.B Rn
Operation
TSTA.B
Before Execution
R1
(no parallel move)
cordingly. The N, Z, V, and C condition codes are calculated based on the 8-bit result. The source op-
erand is not modified.
TSTA.B R1
Prior to execution, the R1 address register contains the value $003AF3, and the 16-bit SR contains the
value $0300. The execution of the TSTA.B R1 instruction compares the value in the low-order 8 bits
of R1 with zero and updates the CCR accordingly. The contents of R1 are not affected.
N
Z
V
C
1 oscillator clock cycle
1 program word
LF
15
— Set if bit 7 of the result is set
— Set if all bits in the result are zero
— Always cleared
— Always cleared
SR
P4
14
Operands
003AF3
Rn
13
P3
0300
P2
12
MR
Test Byte in AGU Register
P1
11
15
C
P0
1
1
10
Instruction Set Details
0
W
;set condition codes for the byte value in R1
I1
1
9
0
Assembler Syntax:
Test byte portion of an AGU register
TSTA.B
I0
8
12
0
SZ
7
11
0
After Execution
6
L
R1
1
5
E
0
S
SR
U
4
CCR
0
8
003AF3
Comments
N
3
7
0
(no parallel move)
0
2
Z
0308
1
V
1
0
4
C
0
TSTA.B
R
3
1
R
A-305
R
0