Datasheet 搜索 > 微处理器 > NXP(恩智浦) > MPC8349EVVAJDB 数据手册 > MPC8349EVVAJDB 开发手册 2/36 页

¥ 977.999
MPC8349EVVAJDB 开发手册 - NXP(恩智浦)
制造商:
NXP(恩智浦)
分类:
微处理器
封装:
TBGA-672
描述:
微处理器 - MPU 8349 TBGA NO PB W/ ENC
Pictures:
3D模型
符号图
焊盘图
引脚图
产品图
页面导航:
应用领域在P1
导航目录
MPC8349EVVAJDB数据手册
Page:
of 36 Go
若手册格式错乱,请下载阅览PDF原文件

Simplified Mnemonics for PowerPC™ Instructions
Overview Overview
1Overview
Simplified (or extended) mnemonics allow an assembly-language programmer to program using more
intuitive mnemonics and symbols than the instructions and syntax defined by the instruction set architecture.
For example, to code the conditional call “branch to an absolute target if CR4 specifies a greater than
condition, setting the LR” without simplified mnemonics, the programmer would write the branch
conditional instruction bc 12,17,target. The simplified mnemonic, branch if greater than, bgt cr4,target,
incorporates the conditions. Not only is it easier to remember the symbols than the numbers when
programming, it is also easier to interpret simplified mnemonics when reading existing code.
Although the original PowerPC architecture documents include a set of simplified mnemonics, these are not
a formal part of the architecture, but rather a recommendation for assemblers that support the instruction set.
Many simplified mnemonics have been added to those originally included in the architecture
documentation. Some assemblers created their own, and others have been added to support extensions to the
instruction set (for example, AltiVec instructions and Book E auxiliary processing units (APUs)). Simplified
mnemonics for new architecturally defined and new implementation-specific special-purpose registers
(SPRs) are described here only in a very general way.
2 Subtract Simplified Mnemonics
This section describes simplified mnemonics for subtract instructions.
2.1 Subtract Immediate
There is no subtract immediate instruction; however, its effect is achieved by negating the immediate
operand of an Add Immediate instruction, addi. Simplified mnemonics include this negation, making the
intent of the computation clearer. These are listed in Table 1.
2.2 Subtract
Subtract from instructions subtract the second operand (rA) from the third (rB). The simplified mnemonics
in Table 2 use the more common order in which the third operand is subtracted from the second.
Table 1. Subtract Immediate Simplified Mnemonics
Simplified Mnemonic Standard Mnemonic
subi rD,rA,value addi rD,rA,–value
subis rD,rA,value addis rD,rA,–value
subic rD,rA,value addic rD,rA,–value
subic. rD,rA,value addic. rD,rA,–value
Table 2. Subtract Simplified Mnemonics
Simplified Mnemonic Standard Mnemonic
1
1
rD,rB,rA is not the standard order for the operands. The order of rB and rA is
reversed to show the equivalent behavior of the simplified mnemonic.
sub[o][.] rD,rA,rB subf[o][.] rD,rB,rA
subc[o][.] rD,rA,rB subfc[o][.] rD,rB,rA
Freescale Semiconductor, I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
nc
.
..
器件 Datasheet 文档搜索
AiEMA 数据库涵盖高达 72,405,303 个元件的数据手册,每天更新 5,000 多个 PDF 文件