Legacy-Free Keyboard/Embedded Controller with SPI and LPC Docking Interface
27.6
Interrupt Select Configuration Register Description
Table 27.7 Interrupt Select Configuration Registers
NAME
REG INDEX
DEFINITION
Interrupt request
level
0x70 (R/W)
Bit [3-0] Select which interrupt level is used for Interrupt 0.
select 0
0x00=no interrupt selected.
0x01=IRQ1
0x02=IRQ2
0x0E= IRQ14
0x0F= IRQ15
All pin-type interrupts are edge high (except ECP/EPP). Each Logical
Device’s interrupts selected through this register physically select the
interrupts to be used by the LPC47N350 for either the Serial IRQ
interface or for the individual pin-type ISA interrupts if selected.
Note: An interrupt is activated by setting the Interrupt Request Level Select 0 register to a non-zero
value AND:
1. for the Serial Port logical device by setting any combination of bits D0-D3 in the IER and by setting
the OUT2 bit in the UART's Modem Control (MCR) Register.
2. for the RTC by (refer to the RTC section of this specification).
3. for the KYBD by (refer to the KYBD controller section of this specification).
27.7
Interrupt and DMA Enable and Disable
Any time the interrupt for a logical block is disabled by a register bit in that logical block, the interrupt
output must be disabled. This is in addition to the interrupt disabled by the Configuration Registers
(activate bit cleared or address outside of valid range or the Interrupt Select register set to 0x00).
27.7.1 Logical Device 4 (Serial Port)
Modem Control Register (MCR) Bit D2 (OUT2) –
When OUT2 is a logic "0", the serial port interrupt is disabled.
27.7.2 Real Time Clock (RTC)
See Chapter 23, "Real-Time Clock," on page 257.
27.7.3 Keyboard Controller (KYBD)
See Chapter 13, "Keyboard Controller," on page 143.
27.8
SMSC-Defined Logical Device Configuration Registers
The SMSC Specific Logical Device Configuration Registers reset to their default values only on hard
resets. These registers are not effected by soft resets. See Section 27.2.4, "Configuration Register
Reset Conditions".
Revision 1.1 (01-14-03)
286
SMSC LPC47N350
DATASHEET
SMSC [ SMSC CORPORATION ]
