Cellular Shield SM5100B

Wireless & IoT
1

Hi all,

I have a question with respect to the datasheet for the shield:

http://www.sparkfun.com/products/9607

If I’m connecting an arbitrary microcontroller to this shield, which UART pins should I be working with?

I’m currently connected to the TXD0 and RXD0 (“6-wire UART”) pins. But I noticed that there’s also the “2-wire”

TXD1 and RXD1 pins.

Does this shield require both sets?

Thanks in advance. Regards,

Ry.

2

Hello,

The shield is setup so you can use either set of TX/RX pins. Pins #2,3 are the default. For Arduino boards this will require a soft serial port to be setup for pins 2,3 on the Arduino board. If you chose to use the RX/TX pins instead, you will need to remove the solder joint just above the RX/TX holes and form a new solder joint between the middle pad and the other (outer) pads. This will place the TX/RX lines on the TX/RX pins instead of pins 2,3.