Description Board Features V2: More flexiable board design, modulized functions: RS-232 function presolder module board power supply function by USB-battery charger board. M2M communication function, Currently support M2M communication module board like SIM7020G SIM7070G SIM7080G Board version V2 Most features similar to V1 board. Based on STM32L151 control chip 1x channel sensor data collection 1x RS233 interface communication 1x M2M Wireless communication USB Charge, battery power supply, low power usage 2x programmable LEDs, and 1x programmable button Board image is shown in color green Documentation of V2 board please see on this page. Board Features V1: Support communicatoin via BC35G NB IOT low power module Frequency Band: B1 / B3 / B5 / B8 / B20 / B28 (B28 is still developing) Cover many common frequency bands, but please check before order. Communicate via UART3 of STM32 Jumper for checking power use. On board extra reserved pins SIM slot on back side of PCB board. RS-232 Port Communicate via UART1 of STM32 Jumper for checking power use. Control by STM32L151 low power microcontroller Jumper for checking power use. PB0 PB1 PB2 PB9 programmable LED PB12 programmable button Reserved UART2 interface. Program SWD port. On board reserved DHT11 temperature sensor port via PA7 On board battery charger controller TP4056 Charge via micro USB. Battery read via resistor divider by STM32 chip PA0 pin. All battery protection: over current, over voltage, etc. For Charge jumper and switch: For charge only: jumper – top, switch – top For battery power only: jumper – Any, switch – bottom For USB power only, removed battery: jumper – bottom, switch – bottom For USB power charging battery together: jumper – bottom, switch – top Documentation of V1 board please see on this page.
