Pcm Interface; Keypad Interface - SimCom SIM800 Hardware Design

SIM800 PCM interface only supports master mode, data length is 16 bits (linear), and PCM clock rate is 256
KHz.
Table 19: PCM Specification
Feature
Line Interface Format
Data length
PCM Clock/Sync Source
PCM Clock Rate
PCM Sync Format
Zero Padding/Sign extension
Data Ordering
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:

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.
SIM800_Hardware Design_V1.10
Specification
Linear(Fixed)
16bits(Fixed)
Master Mode(Fixed)
256Khz(Fixed)
Short sync/Long sync both support
Default Zero Padding
MSB/LSB both support
PCM_IN
PCM_OUT
PCM_SYNC
PCM_CLK
GND
Module
Figure 36: PCM reference circuit
41
Smart Machine Smart Decision
PCMOUT
PCMIN
PCMSYNC
PCMCLK
GND
CODEC
2018-08-13