IRCC SMSC Corporation, IRCC Datasheet - Page 34

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

Output Mux, bits 7 - 6
The
Multiplexer port for the active encoder/decoder
(Table 21). Inactive outputs depend on the state
of the Tx Polarity bit when the Output Mux bits
are both high, otherwise inactive outputs are
always low. The Output Mux bits are equivalent
to the 93X IR Option Register bits 6-7. The IR
Loopback, bit 5
The Loopback bit configures the FIFO and
enables the transmitter/receiver for loopback
testing. The SCE MODES bits must be set to
zero before activating the Loopback bit. When
the Loopback bit is one, the SCE enters a full-
duplex mode with internal loopback capability for
testing. The CRC generator can be selectively
reconfigured for either transmit or receive. The
128-byte FIFO input is connected to the SCE
receiver output, the FIFO output is connected to
the SCE transmit input. For IrDA FIR loopback
tests the Loopback bit must be set to zero to exit
loopback mode. Consumer IR loopback tests
LOOPBACK
Output
BIT
0
0
1
1
1
1
Mux
SELECT
CRC
bits
0
1
0
0
1
1
D7
0
0
1
1
select
Table 22 - Hardware CRC Programming
LOOPBACK TX
Table 21 - IrCC Output Multiplexer
D6
0
1
0
1
CRC BIT
the
X
X
0
1
0
1
Output
Active Device to COM Port (default)
Active Device to IR Port
Active Device to AUX Port
Outputs Inactive
34
MUX. MODE
Register is equivalent to Output Mux bit, D6; Bit
7 (Reserved) in the 93X IR Option Register is
equivalent to Output Mux bit, D7.
have
accommodate Output Multiplexer port selection
through
registers or the Output Mux bits; i.e., the last
write from either source determines the current
port selection and is visible in both registers.
reset the Loopback bit automatically when the Rx
Data Size register reaches zero.
must be made following loopback tests in all
modes to verify the Rx message data in the
FIFO.
Loopback Transmit CRC, bit 4
When the Loopback Transmit CRC bit is set to
one, the CRC generator is used by the
transmitter during loopback testing regardless of
the state of the CRC Select bit. Otherwise, the
CRC generator is connected to the receiver
(Table 22).
No CRC Generation, No CRC Checking
No CRC Generation, No CRC Checking
CRC Generation, No CRC Checking
CRC Checking, No CRC Generation
CRC Generation, No CRC Checking
CRC Generation., CRC Checking
been
HARDWARE DESCRIPTION
either
made
the
in
chip-level
legacy
configuration
devices
Provisions
Provisions
to