10.2.8 Worked Examples: Beta Assembly

TL;DR

The content explains how the Beta processor works, specifically focusing on hexadecimal addressing and instruction execution.

Transcript

As presented in lecture, in this course, we use a simple 32-bit processor called the Beta. The Beta works on 32-bit instruction and data words. However, the addresses in memory are specified in bytes. A byte is made up of 8 bits, so each 32-bit instruction consists of 4 bytes. That means that if you have two instructions A and B in consecutive memo... Read More

Key Insights

• 🫦 The Beta processor utilizes a 32-bit instruction and data word architecture.
• ❓ Memory addresses in the Beta processor are specified in bytes, requiring conversions between bytes and instructions.
• ®️ Instruction execution in the Beta processor involves loading values from memory into registers, performing calculations, and storing the results back into registers.
• 👨‍💻 The provided code demonstrates examples of loading values, arithmetic operations, branching, and bitwise operations.
• 🖐️ Bitwise operations such as shifting and logical operations play a crucial role in manipulating and analyzing data in the Beta processor.
• 🫦 The code provided showcases how binary bits can be counted and manipulated using loops and conditions.
• 🫷 The PUSH instruction in the Beta processor involves incrementing the stack pointer and storing register values onto the stack.

Questions & Answers

Q: How does the Beta processor determine the addresses of consecutive instructions?

In the Beta processor, if instruction A is at address 0x100, then instruction B would be at address 0x104, as each instruction is 4 bytes long.

Q: What happens when a LD operation is performed?

During a LD operation, the value stored at the memory location specified by R31 + c is loaded into register R0.

Q: How is the value of R0 modified in the provided code?

Firstly, R0 is loaded with the value stored at address c, making R0 equal to 0x300. Then R0 is incremented with the constant b, resulting in R0 being equal to 0x504.

Q: What does the provided code do in terms of counting binary ones?

The code counts the total number of ones in the original value loaded from address x. It does this using bitwise operations and a loop, where R1 keeps track of the count.

Summary & Key Takeaways

• The Beta processor is a 32-bit processor that operates on 32-bit instruction and data words.

• Memory addresses are specified in bytes, and each 32-bit instruction consists of 4 bytes.

• The content provides examples of code execution and demonstrates how values are stored and manipulated in registers.