LTE-A Module Series
EM12-G Hardware Design
EM12-G_Hardware_Design 34 / 62
“*” means under development.
3.8. PCIE Interface
Under development
3.9. PCM and I2C Interfaces
EM12-G supports audio communication via Pulse Code Modulation (PCM) digital interface and I2C
interface.
The PCM interface supports the following modes:
Primary mode (short frame synchronization, works as both master and slave)
Auxiliary mode (long frame synchronization, works as master only)
In primary mode, the data is sampled on the falling edge of the PCM_CLK and transmitted on the rising
edge. The PCM_SYNC falling edge represents the MSB. In this mode, the PCM interface supports
256kHz, 512kHz, 1024kHz or 2048kHz PCM_CLK at 8kHz PCM_SYNC, and also supports 4096kHz
PCM_CLK at 16kHz PCM_SYNC.
In auxiliary mode, the data is sampled on the falling edge of the PCM_CLK and transmitted on the rising
edge. The PCM_SYNC rising edge represents the MSB. In this mode, PCM interface operates with a
256kHz PCM_CLK and an 8kHz, 50% duty cycle PCM_SYNC only.
EM12-G supports 16-
bit linear data format. The following figures show the primary mode’s timing
relationship with 8kHz PCM_SYNC and 2048kHz PCM_CLK, as well as the auxiliary mode’s timing
relationship with 8kHz PCM_SYNC and 256kHz PCM_CLK.
NOTE
S