1. ARM processors Adam Hoover

2. ARM processors What is it? Family of 32-bit microcontroller processors Who makes it? ARM has changed their name several times: Acorn RISC Machines (1985) Advanced RISC Machines (1990) ARM Holdings (1998) What is its niche? Mid-high level complexity hand-held consumer electronics PDA’s (1980’s) Cell phones (1990’s) Handheld game devices (2000’s)

3. Example Consumer Products Apple Ipod Nintendo DS TASC ChessMachine Gameboy advance Apple Iphone Apple Newton PDA

4. Processor design, not a chip Core design Chip design & fabrication ARM licenses core designs to other companies OEMs can customize chips ARM provides compilers, development tools, and debugging tools for chip development and product development Nintendo DS

5. ARM chips (examples)

6. ARM processor features ARM1 (1985) to ARM11 and Cortex lines, most having 5+ flavors ARM7 cores • Small number of transistors (~35,000) • No microcode, all instructions hard-wired (no flexibility in ISA) • 3-stage pipeline (simple fetch-decode-execute) • 4-8 KB cache memory, typically unified (data/instruction) • 32-bit ISA (not used for simple control stuff) • 18-56 MHz clock speed ARM extensions • “Thumb” instruction set – 16 bit ISA packed into 32-bit code • “Jazelle” instruction set – java code executed in hardware (instead of JVM)

7. ARM assembly code is dense • C program code: • while (i != j) • { • if (i > j) • i -= j; • else • j -= i; • } • ARM assembly code: • loop CMP Ri, Rj ; set condition "NE" if (i != j) • ; "GT" if (i > j), or "LT" if (i < j) • SUBGT Ri, Ri, Rj ; if "GT", i = i-j • SUBLT Rj, Rj, Ri ; if "LT", j = j-I • BNE loop ; if "NE", then loop multiple pieces of work per instruction

8. ARM chip pricing Core licensing – $200,000 to $10,000,000 depending Some chip examples: Atmel AT91SAM family -- $3/unit qty 10,000 (2005) NXP LPC24xx family -- $8-14/unit qty 1 (2009) Texas Instruments MS470 family - $10-22/unit qty 1 (2009) For further pricing, check www.digikey.com For further information, see www.arm.com