Computers as Components, 2nd Edition

2.2 ARM Processor 59

X 5 1 (represents operand 2):

X 5 0 format:

cond

31 27 25 24 20 19 15 11 0

00 X opcode S Rn Rd Format determined by X bit

11 7 0

8-bit immediate#rot

11 6 4 3 0

#shift Sh 0 Rm

11 7 6 4 3 0

Rm1Sh0Rs

FIGURE 2.4

Format of ARM data processing instructions.

BIGBLOCK % 10

FIGURE 2.5

Pseudo-ops for allocating memory.

2.2 ARM PROCESSOR

In this section, we concentrate on the ARM processor. ARM is actually a family

of RISC architectures that have been developed over many years. ARM does not

manufacture its own VLSI devices; rather, it licenses its architecture to companies

who either manufacture the CPU itself or integrate the ARM processor into a larger ...