IRCC SMSC Corporation, IRCC Datasheet - Page 20

• Manufacturer Part Number: IRCC
• Description: INFRARED COMMUNICATIONS CONTROLLER
• Manufacturer: SMSC Corporation

The SIR Interaction Pulse is controlled by the
IrCC configuration register SIP ENABLE bit and
a timer. The IrCC transmits an SIR Interaction
Pulse every 500ms when the SIP enable is
active, an IrDA FIR mode has been selected,
and the transmitter or receiver is not otherwise
engaged.
Active Frame
SIP Enable
Active SIP
Time
Active SIP
Time
FIGURE 12 - SIR INTERACTION PULSE
SIP
FIGURE 13 - SIP CONTROL TIMING
1.6us
20
Countdown
Reset SIP
SIP Timer
The timer that controls the SIP pulse is reset
whenever 1) the SIP enable is inactive, 2) an
active FIR frame is being transmitted or received
or, 3) during an active SIP pulse. The timer is
decrementing whenever the SIP enable bit is
active and the SIP pulse generator, the
transmitter, and the receiver are inactive. When
the timer reaches zero, the SIP pulse generator
is activated (Figure 13).
Timer
8.7us
SIP Timer
Zero