Smart Machine Smart Decision
SIM800_Hardware Design_V1.10
41
2018-08-13
SIM800 PCM interface only supports master mode, data length is 16 bits (linear), and PCM clock rate is 256
KHz.
Table 19: PCM Specification
Note: User can use AT command control PCM interface, for details please refer to document [1].
4.10.1.
PCM Interface
Refer to the following figure for PCM design:
Module
CODEC
PCMIN
PCMSYNC
PCMOUT
PCMCLK
GND
GND
PCM_IN
PCM_OUT
PCM_SYNC
PCM_CLK
Figure 36: PCM reference circuit
4.11.
Keypad Interface
SIM800 consists of 5 keypad column outputs and 5 keypad row inputs, and it can support two kinds of
connections, the traditional 5*5 keypad matrix and the extended 5*5*2 keypad matrix.
Feature
Specification
Line Interface Format
Linear(Fixed)
Data length
16bits(Fixed)
PCM Clock/Sync Source
Master Mode(Fixed)
PCM Clock Rate
256Khz(Fixed)
PCM Sync Format
Short sync/Long sync both support
Zero Padding/Sign extension
Default Zero Padding
Data Ordering
MSB/LSB both support
