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CP3BT26
IOM2 The IOM-2 Mode bit selects the normal PCM
interface mode or a special IOM-2 mode used
to connect to external ISDN controller devic-
es. The AAI can only operate as a slave in the
IOM-2 mode, i.e. the bit clock and frame sync
signals are provided by the ISDN controller. If
the IOM2 bit is clear, the AAI operates in the
normal PCM interface mode used to connect
to external PCM codecs and other PCM audio
devices.
0 – IOM-2 mode disabled.
1 – IOM-2 mode enabled.
AAIEN The AAI Enable bit controls whether the Ad-
vanced Audio Interface is enabled. All AAI
registers provide read/write access while
(CLKEN = 1) AAIEN is clear. The AAIEN bit is
clear after reset.
0 – AAI module disabled.
1 – AAI module enabled.
CLKEN The Clock Enable bit controls whether the Ad-
vanced Audio Interface clock is enabled. The
CLKEN bit must be set to allow access to any
AAI register. It must also be set before any
other bit of the AGCR can be set. The CLKEN
bit is clear after reset.
0 – AAI module clock disabled.
1 – AAI module clock enabled.
20.7.6 Audio Interrupt Status and Control Register
(AISCR)
The ASCR register is used to specify the source and the
conditions, when the audio interface interrupt is asserted to
the Interrupt Control Unit. It also holds the interrupt pending
bits and the corresponding interrupt clear bits for each audio
interface interrupt source. The CPU bus master has read/
write access to the ASCR register. After reset, this register
is clear.
RXIE The Receive Interrupt Enable bit controls
whether receive interrupts are generated. If
the RXIE bit is clear, no receive interrupt will
be generated.
0 – Receive interrupt disabled.
1 – Receive interrupt enabled.
RXEIE The Receive Error Interrupt Enable bit con-
trols whether receive error interrupts are gen-
erated. Setting this bit enables a receive error
interrupt, when the Receive Buffer Overrun
(RXOR) bit is set. If the RXEIE bit is clear, no
receive error interrupt will be generated.
0 – Receive error interrupt disabled.
1 – Receive error interrupt enabled.
TXIE The Transmit Interrupt Enable bit controls
whether transmit interrupts are generated.
Setting this bit enables a transmit interrupt,
when the Transmit Buffer Almost Empty (TX-
AE) bit is set. If the TXIE bit is clear, no inter-
rupt will be generated.
0 – Transmit interrupt disabled.
1 – Transmit interrupt enabled.
TXEIE The Transmit Error Interrupt Enable bit con-
trols whether transmit error interrupts are gen-
erated. Setting this bit to 1 enables a transmit
error interrupt, when the Transmit Buffer Un-
derrun (TXUR) bit is set. If the TXEIE bit is
clear, no transmit error interrupt will be gener-
ated.
0 – Transmit error interrupt disabled.
1 – Transmit error interrupt enabled.
RXIP The Receive Interrupt Pending bit indicates
that a receive interrupt is currently pending.
The RXIP bit is cleared by writing a 1 to the
RXIC bit. The RXIP bit provides read-only ac-
cess.
0 – No receive interrupt pending.
1 – Receive interrupt pending.
RXEIP The Receive Error Interrupt Pending bit indi-
cates that a receive error interrupt is currently
pending. The RXEIP bit is cleared by writing a
1 to the RXEIC bit. The RXEIP bit provides
read-only access.
0 – No receive error interrupt pending.
1 – Receive error interrupt pending.
TXIP The Transmit Interrupt Pending bit indicates
that a transmit interrupt is currently pending.
The TXIP bit is cleared by writing a 1 to the
TXIC bit. The TXIP bit provides read-only ac-
cess.
0 – No transmit interrupt pending.
1 – Transmit interrupt pending.
TXEIP Transmit Error Interrupt Pending. This bit indi-
cates that a transmit error interrupt is currently
pending. The TXEIP bit is cleared by software
by writing a 1 to the TXEIC bit. The TXEIP bit
provides read-only access.
0 – No transmit error interrupt pending.
1 – Transmit error interrupt pending.
RXIC The Receive Interrupt Clear bit is used to
clear the RXIP bit.
0 – Writing a 0 to the RXIC bit is ignored.
1 – Writing a 1 clears the RXIP bit.
RXEIC The Receive Error Interrupt Clear bit is used
to clear the RXEIP bit.
0 – Writing a 0 to the RXEIC bit is ignored.
1 – Writing a 1 clears the RXEIP bit.
TXIC The Transmit Interrupt Clear bit is used to
clear the TXIP bit.
0 – Writing a 0 to the TXIC bit is ignored.
1 – Writing a 1 clears the TXIP bit.
TXEIC The Transmit Error Interrupt Clear bit is used
to clear the TXEIP bit.
0 – Writing a 0 to the TXEIC bit is ignored.
1 – Writing a 1 clears the TXEIP bit.
7 6 5 4 3 2 1 0
TXEIP TXIP RXEIP RXIP TXEIE TXIE RXEIE RXIE
15 12 11 10 9 8
Reserved TXEIC TXIC RXEIC RXIC