ZHCSAB9E September 2012 – June 2019 DP83848-EP
PRODUCTION DATA.
The interrupt function is controlled via register access. All interrupt sources are disabled by default. Setting bit 1 (INTEN) of MICR (0x11h) will enable interrupts to be output, dependent on the interrupt mask set in the lower byte of the MISR (0x12h). The PWR_DOWN/INT pin is asynchronously asserted low when an interrupt condition occurs. The source of the interrupt can be determined by reading the upper byte of the MISR. One or more bits in the MISR will be set, denoting all currently pending interrupts. Reading of the MISR clears ALL pending interrupts.
Example: To generate an interrupt on a change of link status or on a change of energy detect power state, the steps would be:
When PWR_DOWN/INT pin asserts low, user would read the MISR register to see if the ED_INT or LINK_INT bits are set, i.e. which source caused the interrupt. After reading the MISR, the interrupt bits should clear and the PWR_DOWN/INT pin will deassert.