Intel C2550 FH8065401488912 データシート
製品コード
FH8065401488912
Intel
®
Atom™ Processor C2000 Product Family for Microserver
September 2014
Datasheet, Vol. 2 of 3
Order Number: 330061-002US
495
Volume 2—Serial Interrupt Controller—C2000 Product Family
Architectural Overview
23.2.3
Data Frames
Once the start frame has been initiated, the SERIRQ peripherals start counting frames
based on the rising edge of
. Each of the IRQ DATA frames consists of
exactly three phases. Each phase is one LPC clock period:
• Sample Phase - During this phase, a device drives
low if its
corresponding interrupt signal is low. If its corresponding interrupt is high, then the
device tri-states the
line (lets it float).
remains high due to the pull-up resistors required on the platform board.
• Recovery Phase - During this phase, a peripheral device drives
high if
it was driven low during the sample phase. If it was not driven during the sample
phase, it remains tri-stated in this phase.
• Turn-around Phase - The device tri-states
23.2.4
Stop Frame
After the data frames, a stop frame is driven by the serialized interrupt controller.
23.2.5
Serial Interrupts Not Supported
Four interrupts are on the serial stream which are not supported by the serialized
interrupt controller:
• IRQ0: heartbeat interrupt generated by counter 0 of the internal 8254
Programmable Interval Timer (PIT).
• IRQ8#: the Real Time Clock (RTC) interrupt is only generated internally.
• IRQ13: this interrupt indicates floating point error and is not supported.
• IRQ14: this interrupt is only generated by the Serial ATA (SATA) controller in SATA
• IRQ13: this interrupt indicates floating point error and is not supported.
• IRQ14: this interrupt is only generated by the Serial ATA (SATA) controller in SATA
legacy mode.
The serialized interrupt controller ignores the states of these interrupts if detected in
the IRQ data stream.
Table 23-3. SERIRQ, Stop Frame Width to Operation Mode Mapping
Stop Frame Width
Next Mode
Two LPC clocks
Quiet Mode - Indicating that any SERIRQ device may initiate a start frame.
Three LPC clocks
Continuous Mode - Only the interrupt controller may initiate a start frame.