The Silent Invasion
Dec 21, 2015
You own an ARM machine!(or several dozen)
• Over 75% of the embedded device market is powered by ARM
• ARM is small
• Requires low power
• Efficient performance
• CHEAP TO MANUFACTURE
Odd features of the ARM Model
• Every instruction has a condition code
This means that you don’t necessarily have to branch around.
• Shifting and rotating can be embedded in other arithmetic instructions.
•An actually useful interrupt system
Registers
• ARM is load-store
• Has 37 registers
• You can only see 16 in main software mode
• You can only really use the first 13
• R13, R14, and R15 are the stack pointer, link pointer, and the PC respectively
Instructions
• ADD – Standard Addition• ADC – Add with carry• QADD – Saturated add• QDADD – Double saturated add
• B – Branch… if you don’t know what this does, good luck on the final
• BL – Branch and link