User's Manual

eUniStone
PBA 31309
eUniStone Interfaces
User’s Manual Intel Public 16
Hardware Description Revision 1.0, 1-Feb-2013
3.0 eUniStone Interfaces
3.1 UART Interface
The UART interface is the main communication interface between the host and
eUniStone. AT commands are described in detail in the AT Commands specification [1].
The interface consists of four UART signals and two LPM control signals as shown in
Figure 4.
Figure 4. UART Interface
3.1.1 UART
The lines UARTTXD and UARTRXD are used for commands, responses and data. The
lines UARTRTS and UARTCTS are used for hardware flow control. A separate supply
voltage, VDDUART, defines the UART reference levels to fit any system requirements.
3.1.1.1 Baud Rates
The UART baud rate can be configured with the BD_DATA parameter UART_Baudrate.
The module is programmed for a default baudrate of 115200 baud. Reprogramming of
the EEPROM configuration is possible by AT commands at manufacturing time of the
end product. The baudrate written to EEPROM will be used each time eUniStone starts
or, HW or SW reset is done.
The host is also able to change the baudrate temporarily with an AT command. This
baudrate is used by eUniStone until a HW or SW reset is done, when it will change back
to the baudrate stored in the EEPROM.
eUnistone_UART_Interface.vsd
UARTTXD
UARTRXD
UARTRTS
UARTCTS
WAKEUP_BT
WAKEUP_HOST
UARTTXD
UARTRXD
UARTRTS
UARTCTS
P0.14 input
P0.0 output
Host eUniStone