Nios II Classic Software Developer’s Handbook

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

6.13.2. Use Reduced Device Drivers

Some devices provide two driver variants, a fast variant and a small variant. The feature sets provided by these two variants are device specific. The fast variant is full-featured, and the small variant provides a reduced code footprint.

By default the HAL always uses the fast driver variants. You can select the reduced device driver for all hardware components, or for an individual component, through HAL BSP settings.

The small footprint option might also affect other peripherals. Refer to each peripheral’s data sheet for complete details of its driver’s small footprint behavior.

Table 33.  Intel FPGA Peripherals Offering Small Footprint Drivers
Peripheral Small Footprint Behavior
UART Polled operation, rather than IRQ-driven
JTAG UART Polled operation, rather than IRQ-driven
Common flash interface controller Driver excluded in small footprint mode
LCD module controller Driver excluded in small footprint mode
EPCS serial configuration device Driver excluded in small footprint mode