SIM5218E Hardware Design
SIM5218E_ Hardware Design_V1.06
2012.09.21
51
Module and an external codec or DSP. Both the PCM interface modes, auxiliary and primary, use
the same SIM5218E pins. The PCM pin assignment is shown in the table below.
Note: Please reference document [22] for detailed information of PCM Application Note.
Table 27 : PCM pin assignment
Pins
Pin
No.
AUX_PCM
functionality
Primary_PCM
functionality
Description
PCM_CLK/GPIO3
31
AUX_PCM_CLK
PCM_CLK
PCM clock for PCM
communication to
external codec
PCM_SYNC/GPIO2
30
AUX_PCM_SYNC
PCM_SYNC
PCM data strobe for
PCM
communication to
external codec
PCM_DIN/GPIO0
65
AUX_PCM_DIN
PCM_DIN
PCM data input to
the Module (Rx)
PCM_DOUT/GPIO5
33
AUX_PCM_DOUT PCM_DOUT
PCM data output
from the Module
(Tx)
The default PCM interface on power up is the
auxiliary
PCM interface. Under PCM, the data
is output on the rising edge of PCM_CLK and sampled at the falling edge of PCM_CLK.
Primary PCM is disabled at power off or when RESET is asserted.
After the PCM interface is configured, PCM Rx data will be routed from the external codec Mic
through the DSP encode path in the Module. PCM Tx data will be routed through the DSP decode
path to the external codec speaker.
In master Mode, the Module drives the clock and sync signals that are sent out to the external
codec via the PCM Interface. When in slave mode, the external codec drives the clock and sync
signals that are sent to the Module.
PCM formats can be chosen by AT command.
Many parameters of external codec audio channel are not available. Only RxVolume, FIR, are still
available after enabling PCM.
Table 30
: PCM external codec
Characteristics
Audio Device no.
AT+CSDVC=
4
Name
External Codec
micAmp No available
txGain
No available
txVol
No available
Default
MIC path
Parameters
txFilter
0xff33, 0x05d8,0xf488, 0x0af3,
