Quectel BC68 Hardware Design

GSM/GPRS Module Series
M66 Hardware Design
M66_Hardware_Design Confidential / Released 45 / 80
3.9. PCM Interface
M66 supports PCM interface. It is used for digital audio transmission between the module and the device.
This interface is composed of PCM_CLK, PCM_SYNC, PCM_IN and PCM_OUT signal lines.
Pulse-code modulation (PCM) is a converter that changes the consecutive analog audio signal to discrete
digital signal. The whole procedure of Pulse-code modulation contains sampling, quantizing and
encoding.
Table 12: Pin Definition of PCM Interface
3.9.1. Configuration
M66 module supports 13-bit line code PCM format. The sample rate is 8 KHz, and the clock source is 256
KHz, and the module can only act as master mode. The PCM interface supports both long and short
synchronization simultaneously. Furthermore, it only supports MSB first. For detailed information, please
refer to the table below.
Table 13: Configuration
AOUT2
Output
Single-ended
Load resistance
32
Load
Resistance
Reference level
0
2.4
Vpp
Pin Name
Pin No.
Description
PCM_CLK
30
PCM clock output
PCM_SYNC
31
PCM frame synchronization output
PCM_IN
32
PCM data input
PCM_OUT
33
PCM data output
PCM
Line Interface Format
Linear
Data Length
Linear: 13 bits
Quectel
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Quectel BC68 Specifications

General

Brand	Quectel
Model	BC68
Category	Control Unit
Language	English