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3.11
PCM Interface
SIM5320J-TE provides hardware PCM interface for external codec. The PCM interface enables
communication with an external codec to support hands-free applications. SIM5320J-TE PCM interface
can be used in two modes: the default mode is auxiliary PCM (8 KHz long sync mode at 128 KHz PCM
CLK); the other mode is primary PCM (8 KHz short sync mode at 2048 KHz PCM CLK). In short-sync
(primary PCM) mode, SIM5320J-TE can be a master or a slave. In long-sync (auxiliary PCM) mode,
SIM5320J-TE is always a master. SIM5320J-TE also supports 3 kinds of coding formats: 8 bits (
-law or
A-law) and 16 bits (linear).
Note: PCM interface is multiplexed from GPIO (default setting). The AT command “AT+CPCM” is used to switch
between PCM and GPIO functions. Please refer to document [22] and document [1] for details.
3.11.1
Pin Description
Table 28: Electronic characteristic
DC Characteristics
Pin name
Min
Typ
Max
PCM_CLK
-0.3
2.6
2.9
PCM_SYNC
-0.3
2.6
2.9
PCM_DOUT
-0.3
2.6
2.9
PCM_DIN
-0.3
2.6
2.9
Table 29: Pin description
Pins
Pin No.
AUX_PCM
functionality
Primary PCM
functionality
Description
PCM_DIN/GPIO0
54
AUX_PCM_DIN
PCM_DIN
PCM data input
PCM_SYNC/GPIO2 53
AUX_PCM_SYNC
PCM_SYNC
PCM data synchrony
PCM_DOUT/GPIO5
55
AUX_PCM_DOUT
PCM_DOUT
PCM data output
PCM_CLK/GPIO3
52
AUX_PCM_CLK
PCM_CLK
PCM data clock
3.11.2
Signal Description
The default PCM interface in SIM5320J-TE is the auxiliary PCM interface. The data changes on the high
level of PCM_CLK and is sampled at the falling edge of PCM_CLK in one period. Primary PCM is
disabled after every power-on or every reset event. So user must use AT command to enable the primary
SIM5320J-TE_Hardware Design_V1.01
2012-11-09
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