Update SIM900 to SIM800F in Your IoT Project

Update SIM900 to SIM800F in Your IoT Project

There the SIM900 GPRS/GPS module is popularly used in IoT projects, but as the SIM900 module is EOL, if you find them on sale in the market, the price is high. So there are plenty of projects that need to be updated.

As the producer SIMCom suggested, the SIM800F is a pin-to-pin upgrade version for the SIM900. But if you indeed solder the SIM800F module directly on the boards that previously works with SIM900, there high possibility that, the SIM800F does not work.

That is, the SIM800F is not fully compatible with the SIM900!

Compares the pins definition:

                           (SIM800F Top View)                                       (SIM900 Top View)

There the most significant difference is: 


That is:
1. (mandatory)For SIM900, the Pin_2 can be NC, but if using SIM800F, it should be GND connected or the SIM800F will not work.
2. (Optional)For SIM900, the Pin_23 NC, but Pin_23 can be KPLED control for SIM800F.
3. (Optional) For SIM900, the Pin_24 NC, but Pin_23 can be VBUS
4. (Optional) Pin_27/28 different definition, from UART to USB;
5. (mandatory) for SIM900, PIN_53 needs to be GND connected, while for SIM800F, it is BT-ant, or NC is not used.

To make the SIM800F work as a SIM900 substitute item, these 2 pins need to be updated:


With these 2 hardware modifications, the SIM800F works with GPRS/GPS connections.

In SIMCom+ MCU usage, with AT commands, there are also some AT commands differences, please check this.

This article is first published by Makerfabs.