Intel® Core™ Ultra Series 3 Processors I/O Registers
| ID | Date | Version | Classification |
|---|---|---|---|
| 872352 | 04/14/2026 | 001 | Public |
REG IER (IER) – Offset 4
Interrupt Enable Register. IER mode is only available when LCR register [7] (DLAB bit) = 0.
| Bit Range | Default | Access | Field Name and Description |
|---|---|---|---|
| 31:8 | 0h | RO | Res_31_8 (Res_31_8) Reserved |
| 7 | 0h | RW | PTIME (PTIME) THRE Interrupt Mode Enable: This is used to enable/disable the generation of THRE |
| 6:5 | 0h | RO | Res_6_5 (Res_6_5) Reserved |
| 4 | 0h | RW | ELCOLR (ELCOLR) This bit controls the method for clearing the status in the LSR register. This is applicable only for Overrun Error, Parity Error, Framing Error and Break Interrupt status bits. |
| 3 | 0h | RW | EDSSI (EDSSI) Enable Modem Status Interrupt: This is used to enable/disable the generation of |
| 2 | 0h | RW | ELSI (ELSI) Enable Receiver Line Status Interrupt. This is used to enable/disable the generation |
| 1 | 0h | RW | ETBEI (ETBEI) Enable Transmit Holding Register Empty Interrupt. This is used to enable/disable the |
| 0 | 0h | RW | ERBFI (ERBFI) Enable Received Data Available Interrupt. This is used to enable/disable the |