Embedded systems: Memory Mapped I/O Memory mapped I/O is a method - - PowerPoint PPT Presentation

▶

May 29, 2023 159 likes •229 views

Embedded systems: Memory Mapped I/O Memory mapped I/O is a method of performing input/output operations between the central processing unit (CPU) and peripheral devices CPU CPU bus SPI MEMORY Module A Memory mapped I/O uses the same

SLIDE 1

Embedded systems: Memory Mapped I/O

SLIDE 2

Memory mapped I/O is a method of performing input/output operations between the central processing unit (CPU) and peripheral devices

CPU

MEMORY

SPI

CPU bus

Module A

SLIDE 3

Memory mapped I/O uses the same address space to address both memory and I/O devices

CPU

MEMORY

SPI

CPU bus

SPI Memory UART

. . .

Module A Module N 0x00000000 0x00005000 0x00005050 0x00005070 0x0F006000

Module A

4 GB

0xFFFFFFFF

SLIDE 4

The Nios II provides memory mapped I/O access

SLIDE 5

SPI Memory UART

. . .

PIO Module N 0x00005070

I/O 1 write(addr,reg,data) write(0x5070,0,0x1)

0x00000000 0xFFFFFFFF

Perform I/O operations by writing to memory location

SLIDE 6

PIO register map

Source: http://www.altera.com/literature/ug/ug_embedded_ip.pdf

The Nios II CPU controls and communicates with a memory mapped module through a set of 32-bit registers