dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 656

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

ZXTA.B
Operation:
0 → D[23:8]
Description: Take the byte that is located in the low-order 8 bits of the destination AGU address register, and zero
Example:
Explanation of Example:
Condition Codes Affected:
Instruction Fields:
Instruction Opcodes:
Timing:
Memory:
A-312
ZXTA.B Rn
Operation
ZXTA.B
Before Execution
R2
extend it to fill all 24 bits.
ZXTA.B R2
Initially, the R2 AGU register holds the value $1C70F3. After the ZXTA.B R2 instruction is execut-
ed, zeros are replicated through the high-order 16 bits. The result is $0000F3.
The condition codes are not affected by this instruction.
1 oscillator clock cycle
1 program word
(no parallel move)
Operands
1C70F3
Rn
Zero Extend Byte in AGU Register
DSP56800E Core Reference Manual
15
1
C
1
0
; sign extend byte in R2
W
1
0
Assembler Syntax:
ZXTA.B
Zero extend the value in an AGU register from bit 7
12
0
11
0
After Execution
R2
1
0
D
1
8
0000F3
Comments
7
1
(no parallel move)
0
Freescale Semiconductor
1
1
4
ZXTA.B
R
3
0
R
R
0