今天翻了半天一直在看implicit declaration of 'ALT_IRQ_REGISTER'警告。后来根据Nios_II_Software_Developer’s_HandBook找到了HAL API Reference。
根据Document Revision History:
November 2009 9.1.0
Document new enhanced HAL interrupt API functions: alt_ic_irq_disable(),
alt_ic_irq_enable(), alt_ic_irq_enabled(), and alt_ic_isr_register().
Deprecate legacy HAL interrupt API functions alt_irq_disable(),
alt_irq_enable(), alt_irq_enabled(), and alt_irq_register().
This function is part of the legacy HAL interrupt API, which is deprecated. Altera recommends using the enhanced HAL interrupt API.