Nios II Classic Software Developer’s Handbook

ID 683282
Date 5/14/2015
Public
Document Table of Contents

5.2.4.1. Device Model Classes

The HAL provides models for the following classes of devices:
  • Character-mode devices—Hardware peripherals that send and/or receive characters serially, such as a UART.
  • Timer devices—Hardware peripherals that count clock ticks and can generate periodic interrupt requests.
  • File subsystems—A mechanism for accessing files stored in physical device(s). Depending on the internal implementation, the file subsystem driver might access the underlying device(s) directly or use a separate device driver. For example, you can write a flash file subsystem driver that accesses flash using the HAL API for flash memory devices.
  • Ethernet devices—Devices that provide access to an Ethernet connection for a networking stack such as the Altera-provided NicheStack® TCP/IP Stack - Nios II Edition. You need a networking stack to use an ethernet device.
  • Direct memory access (DMA) devices—Peripherals that perform bulk data transactions from a data source to a destination. Sources and destinations can be memory or another device, such as an Ethernet connection.
  • Flash memory devices—Nonvolatile memory devices that use a special programming protocol to store data.