Pcm Interface; Keypad Interface - SimCom SIM800L Hardware Design

PCM_CLK 29
PCM_OUT 30
PCM_SYNC 65
PCM_IN 66
SIM800L PCM interface only supply master mode, data length is 16 bits (linear)，PCM clock rate is 256KHz.
Table 21: PCM specification
Parameter
Line Interface Format
Data length
PCM Clock/Sync Source
PCM Clock Rate
PCM Sync Format
Zero Padding/Sign extension
Data Ordering
Note: Customer can use AT command control PCM interface. For detail, please refer to document [1].
4.9.1.

PCM Interface

Refer to the following figure for PCM design:

4.10. Keypad Interface

The keypad interface consists of 5 keypad column outputs and 5 keypad row inputs. with total 5*5*2, which is 50
keys. Module has two connections, which supports 25 keys and anther supports 50 keys.
SIM800L(MT6261)_Hardware Design_V1.01
PCM clock
PCM data output
PCM synchrony
PCM data input
Specification
Linear(Fixed)
16bits(Fixed)
Master Mode(Fixed)
256KHz(Fixed)
Short sync/Long sync both support
Zero Padding(Fixed)
MSB/LSB both support
PCM_IN
PCM_OUT
PCM_SYNC
PCM_CLK
GND
Module
Figure 36: PCM reference circuit
Smart Machine Smart Decision
PCMOUT
PCMIN
PCMSYNC
PCMCLK
GND
CODEC
40 2016-07-07