EMC12 ETC2 [List of Unclassifed Manufacturers], EMC12 Datasheet - Page 37

• Manufacturer Part Number: EMC12
• Description: Audio Interface for the EmPack System
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

1.5.2 Data Conversion Mode and Sampling Rate
09 Jan 2006
The functions below control the value of the CODEC’s register that sets its DAC attenuation:
The following two functions in the EmPack API control the analog-to-digital and digital-to-analog
conversion process. The two parameters are the data conversion format and the sampling rate.
The functions operate on registers inside the CS4231 CODECs as well as setting register bits in
the EMC12’s FPGA controlling the interface between the CODEC and the TDM subsystem.
These functions may be applied to an individual resource or the EMC12 broadcast resource.
Note, however, that these operations apply to both channels in the CODEC for an individual
resource. Therefore, setting the data conversion format or sampling rate for CODEC resource
‘a’ will set the same parameters for channel ‘b’. Setting these parameters for channel ‘c’ will
also set them for channel. ‘d’, etc.
The EmSetCodecCvMode function controls the digital data format (conversion mode) used by
the CODEC. The modes for input and output are specified as separate arguments,
InputCvMode and OutputCvMode, and may be different if desired. The valid values for the
conversion modes are defined as macros in the emapi.h. They are:
)
int
EmSetCodecAdcGain (
)
int
EmSetCODECDacAtten (
)
int
EmSetCodecCvMode (
)
BOOL MicGain
RESOURCE_HANDLE Resource,
int AdcGain
RESOURCE_HANDLE Resource,
int DacAtten
RESOURCE_HANDLE Resource,
int InputCvMode
int OutputCvMode
EM_CS4231_LIN8
EM_CS4231_LIN8_D
EM_CS4231_LIN16
EM_CS4231_LIN16_B
EM_CS4231_ULAW
EM_CS4231_ALAW
Communication Automation Corporation
EMC12 Hardware Reference Manual
EmGetCodecCvMode (
Unsigned 8-bit Linear
Unsigned 8-bit Linear with Dither (for Input only)
Signed 16-bit Linear
Signed 16-bit Linear, Big Endian (byte reversed)
A-Law Companded, 8-bit
-Law Companded, 8-bit
)
int
EmGetCodecAdcGain (
)
int
EmGetCODECDacAtten (
)
int
)
BOOL *MicGain
RESOURCE_HANDLE Resource,
int *AdcGain
RESOURCE_HANDLE Resource,
int *DacAtten
RESOURCE_HANDLE Resource,
int *InputCvMode
int *OutputCvMode
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