I am using an STM32F100xx MCU and I want to communicate via UART with a GPS module, specifically the A7 Thinker GPS GPS Module with A7 Thinker from Aliexpress
This module, when a 9V battery is used, operates at 3.6 - 4.2V .
The UART pins of the STM32F100xx MCU are 5V tolerant. Can I use UART communication directly without level shifters to 3.3V?