SIM808

Minicom configuration (communication between rpi and sim808)

A -    Serial Device      : /dev/ttyAMA0                              |
B - Lockfile Location     : /var/lock                                 |
C -   Callin Program      :                                           |
D -  Callout Program      :                                           |
E -    Bps/Par/Bits       : 9600 8N1                                  |
F - Hardware Flow Control : No                                        |
G - Software Flow Control : Yes                                       |

hardware wiring

RPI

https://www.raspberrypi.org/documentation/usage/gpio/

PIN 15: RX
PIN 14: TX
PIN GROUND: GROUND

SIM808

sim808 evb-v3.2

RPI TX to RXD
RPI RX to TXD
RPI GROUND to GROUND

Notice: TX and RX ports are crossed.

Software config

raspi-config

- enable serial interface
- disable serial login shell

Reboot

In case of issues have a look to this SO post

tests

> minicom

Welcome to minicom 2.7

OPTIONS: I18n
Compiled on Apr 22 2017, 09:14:19.
Port /dev/ttyAMA0, 11:19:28

Press CTRL-A Z for help on special keys

AT
OK

sources

SIM800_Series_AT_Command_Manual_V1.09.pdf

http://acoptex.com/project/264/basics-project-053d-sim808-gsm-gprs-gps-bluetooth-evolution-board-evb-v32-at-acoptexcom/

https://wiki.dfrobot.com/SIM808_GPS_GPRS_GSM_Shield_SKU__TEL0097