I have been unable to find any documentation relation to I2C connectivity.
The brief reference to it in the Hardware Design guide (V1.4) suggests that I2C is only used in the “Telematics” version when relating to the digital audio (PCM) function.
Is this true?
Thanks for your inquiry in Quectel forum.
Please check the following document, it already modified. Thanks!
Quectel_EC21_Hardware_Design_V1.7.pdf (1.5 MB)
According to Note 2 on Page 54;
- EC21 works as a master device pertaining to I2C interface.
So, the I2C interface is not available for a host to talk to the EC21. This leaves USB and the UART.