Nios® V Processor Software Developer Handbook

ID 743810
Date 7/08/2024
Public
Document Table of Contents

7.11.2. Use Small Variant 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:
  • Fast variant is full-featured with standard code footprint
  • Small variant have smaller code footprint and less features

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

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 32.  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