Figure 3-30. Audio Tx Path Block Diagram - Motorola APX 1000 Detailed Service Manual

3-40
OMAP DSP
SSI
MCBSP1
I2C
Reset Out
DSP SPI
The external microphone path will also be supported by the TI AIC33 CODEC, using the LINE1LP
pin on the IC. The LINE1LP is multiplexed with the MIC3R within the CODEC, and selected as the
input when the external microphone path is chosen as the TX audio source. Similar to the internal
microphone signals, the TI CODEC amplifies and samples the external microphone signal. The
digital data is also sent to the OMAP1710's DSP through the McBSP1 port using the audio SSI bus.
MAKO
SSI
VC_DCLK
VC_FSYNC
VC_TX
VC_RX
MIC BIAS
Audio Stereo Codec (TI AIC33)
SSI
LEFT
ADC
I2C
Reset
RIGHT
ADC
SPI

Figure 3-30. Audio TX Path Block Diagram

Theory of Operation
Note: All three microphones will be
routed to the AIC33 CODEC. In Tx
mode, MAKO will only be used to
generate the microphone bias. Both
internal microphones will be sampled
on adjacent SSI slots. The external
microphone can be sampled on either
slot.
1
4
Line 1L
5
Mic 3R
6
Mic 3L
Test Point Descriptions
: Controller
External/
Accessory
Microphone
Internal
Microphone 1
Internal
Microphone 2
Board Overlay