User's Manual

PCS3_HD_v01.000-03
Confidential / Preliminary
Page 45 of 101
2013-10-21
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PCS3 Hardware Interface Description
3.9 Digital Audio Interface
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3.9 Digital Audio Interface
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PCS3 supports a digital audio interface that can be employed either as pulse code modulation
(see Section 3.9.1) or as inter IC sound interface (see Section 3.9.2). Operation of these inter-
face variants is mutually exclusive.
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3.9.1 Pulse Code Modulation Interface (PCM)
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PCS3’s PCM interface can be used to connect audio devices capable of pulse code modula-
tion. The PCM functionality allows the use of a codec like the Freescale MC145483. Using the
AT^SAIC command you can activate and configure the PCM interface (see [1]).
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The PCM interface supports the following modes:
• Master mode, slave mode
• Short frame synchronization
• 256kHz, 512kHz and 2048kHz bit clock
• Additional master mode with 128kHz, long frame synchronization
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For the PCM interface configuration the parameters <clock>, <mode> <frame_mode> and
<ext_clk_mode> of the AT^SAIC command can be configured. The following table lists possi-
ble combinations:
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Table 11: Configuration combinations for the PCM interface
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Configuration <clock> <mode> <frame_mode> <ext_clk_mode>
Master, 128kHz, long frame 0 0 1 0 or 1
Master, 256kHz, short frame 1 0 0 0 or 1
Master, 512kHz, short frame 2 0 0 0 or 1
Master, 2048kHz, short frame 3 0 0 0 or 1
Slave, 256kHz, short frame 1 1 0 1
Slave, 512kHz, short frame 2 1 0 1
Slave, 2048kHz, short frame 3 1 0 1
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In slave mode <clock> must be set according the source clock frequency. Being in master
mode clock and frame synchronization signals may be permanently switched on by
<ext_clk_mode> parameter. These signals may be used for clocking digital audio periphery
outside a call.
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Table 12 lists the available PCM interface signals.
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Table 12: Overview of PCM signal functions
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Signal name on
SMT application
interface
Signal
configuration
inactive
1
Signal
direction:
Master
Signal
direction:
Slave
Description
PCM_OUT PD O O
PCM Data from PCS3 to external
codec
PCM_IN PD I I
PCM Data from external codec to
PCS3