原创 ADI DSP基础教程：Blackfin的内核之ALU（BF533为例）

ALU当然是处理器内核的一个重要单元，我们来看图说话：（基础中的基础，没有录视频教程）

Blackfin的内核之ALU（BF533为例）





再来一张放大图：

    

Blackfin的内核之ALU（BF533为例）

ALU的全称是Arithmetic Logic Unit！中文是不是应该叫算术逻辑单元，还是来英文吧。

Two 40-bit ALUs operating on 16-bit, 32-bit, and 40-bit input operands and output 16-bit, 32-bit, and 40-bit results.

Functions

Fixed-point addition and subtraction

Addition and subtraction of immediate values

Accumulator and subtraction of multiplier results

Logical AND, OR, NOT, XOR, bitwise_XOR, Negate

Functions: ABS, MAX, MIN, Round, division primitives

Supports conditional instructions

Four 8-bit video ALUs ：Explained in more detail as part of Advanced Instructions section

ALU Operations ：Conditional Code (CC) Bit in ASTAT

CC bit is used in several instructions

Action taken in the instruction depends on the value of CC

If cc jump here; //if cc = 1, jump to label “here”

If cc r3 = r0; // perform move if cc=1

CC bit value is based on a comparison of two registers, pointers or accumulators；CC bit can be moved to and from a data register or ASTAT bit；CC bit can be negated；

下一篇就准备简单说一下MAC，全称：MULTIPLY-ACCUMULATORS

任何ADI DSP的问题，均可联系OP的QQ：5516164，微信：OpenADSP

OP的网站：www.openadsp.com

OP的论坛：www.openadsp.com/bbs

OP的官方淘宝店：https://shop108086345.taobao.com/

ADI DSP中文资料全集（含视频教程）的淘宝链接：https://item.taobao.com/item.htm?spm=a1z10.5-c.w4002-5192690539.12.Ck3v8f&id=39935721554