LISA-U series - System Integration Manual
UBX-13001118 - R17
Advance information
System description
Page 68 of 190
The UART wake up via data reception configuration is not active on the
TXD
input, and therefore all the data
sent by the DTE is lost, if:
o
AT+UPSV=2 is set with HW flow control disabled, and the
RTS
line is set OFF
o
AT+UPSV=3 is set, regardless HW flow control setting, and the
DTR
line is set OFF
Figure 30 and Figure 31 show examples of common scenarios and timing constraints:
AT+UPSV=1 power saving configuration is active and the timeout from last data received to idle-mode start
is set to 2000 frames (AT+UPSV=1,2000)
Hardware flow control is disabled
Figure 30 shows the case where the module UART is disabled and only a wake-up is forced. In this scenario the
only character sent by the DTE is the wake-up character; as a consequence, the DCE module UART is disabled
when the timeout from last data received expires (2000 frames without data reception, as the default case).
OFF
ON
DCE UART is enabled for 2000 GSM frames (~9.2 s)
time
Wake up time: ~20 ms
time
TXD input
Wake up character
Not recognized by DCE
UART
OFF
ON
Figure 30: Wake-up via data reception without further communication
DCE UART is enabled for 2000 GSM frames (~9.2s)
after the last data received
time
Wake up time: ~20 ms
time
Wake up character
Not recognized by DCE
Valid characters
Recognized by DCE
OFF
ON
TXD input
UART
OFF
ON
Figure 31: Wake-up via data reception with further communication
