3/29: Processors

1. 3/29: Processors • Roll Call • Lecture: CPU’s • Other (?)

2. CPU: General • The Microprocessor or CPU (Central Processing Unit) is the “brains” of the computer. • All other components (RAM, monitor, disk drive) act like bridges to link you & the processor.

3. CPU: the Helpers • Coprocessors are also in PC’s. • They handle functions like graphics, 3-D acceleration, and sound cards. • This helps take away some of the load off the main processor.

4. Pentium Parts Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

5. Pentium Parts Branch Predictor Unit 8K Code Cache The BIU sorts through the data and code that is sent from RAM. The code is sent one way, and the data is sent the other way. After the processing, the BIU will send the processed data back to RAM. Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

6. Pentium Parts Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit The caches, one for data and one for code, are the “ready rooms” for the ALU’s. ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

7. Pentium Parts Branch Predictor Unit 8K Code Cache The Branch Predictor Unit decides which ALU will be quicker at processing the next instruction. Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

8. Pentium Parts The Instruction Prefetch Buffer retrieves the BPU-specified code from the cache. The Decode Unit converts the code into ALU-usable instructions. Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

9. Pentium Parts Branch Predictor Unit The Floating Point Unit processes the numbers after the decimal point, as well as other specified commands. 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

10. Pentium Parts The Arithmetic Logic Units process the data using specially wired circuits and transistors. Their output is sent to the registers, a kind of “electronic scratch pad.” Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

11. Pentium Parts The Data Cache transfers the processed information from the registers back to the BIU, which sends it to the RAM. Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

12. Pentium Parts Branch Predictor Unit 8K Code Cache Instruction Prefetch Buffer & Decode Unit BIU Bus Interface Unit ALU ALU Floating Point Unit Registers To RAM 8K Data Cache

13. 3/31: Types of Pentium Processors • Pentium • Pentium Pro • Pentium MMX • Pentium Celeron • Pentium II • Pentium III