A BEE Socket is introduced in MS14N to connect more modules. Definition is as below:
The xBee socket can power a plug-in module via the BEE_VIN pin. this pin can be 3.3v or 5v, depends on where to put jumper on BEE-VIN header.
The BEE_TXD and BEE_RXD has below connection
BEE_TXD <--> 3_state-Buffer <--> Linux Module UART_RX BEE_RXD <--> 3_state-Buffer <--> Linux Module UART_TX
In MS14N v1.3, the 3_state_buffer enable/disable is controlled by GPIO27, if GPIO27 is set high, the Linux UART is connected to the BEE UART, if GPIO27 is set low , the Linux UART is disconnected from Bee socket
This connection makes it compatible with the most xBee or Bluetoole module in BEE socket format,
A separate USB Interface is also available in the BEE socket to support USB module.
SIM Card Pins:
They are reserved for SIM card connection.