SkyTraq PX1172R - Page 6

6
www.skytraq.com.tw
20
RTK_STAT 
Status signal
0:RTKFix
Blink  :RTKFloat
1:otherwise
21,22,23,24,25
NC
Noconnection,emptypin
26
RXD2
UARTserialdatainput,3.3VLVTTL.
OnesimplexasynchronousserialUARTportisimplemented.ThisUARTinputis
normallyforsendingRTCM‐SC104correctiondataorbasestationSkyTraqraw
measurementdatatothereceiver at115200baudrate.In the idlecondition,
thispinshouldbedrivenHIGH.Ifthedrivingcircuitryispoweredindependently
ofPX1172R,ensurethatthispinisnotdriventoHIGHwhenPX1172Risputto
sleep,ora10K‐ohmseriesresistorcanbeaddedtominimizeleakagecurrent.
27
TXD2
UARTserialdataoutput,3.3VLVTTL.
Notused.
28,29,30,31
NC
Noconnection,emptypin
32
GND
Ground
33,34
VDD33 
Powersupply,3.3VDC
35
NC
Noconnection,emptypin
36
V_BCKP 
Backupsupplyvoltage forinternalRTCand backup SRAM, 1.3V~ 3.6V. VBAT
must be applied whenever VCC is applied. This pin should be powered
continuously to minimize the startup time. If VCC and V_BCKP are both
removed,thereceiverwillbeinfactorydefaultmodeuponpowerup,alluser
configurationsetislost.Forapplicationsthedoesnotcarecoldstartingevery
time,thispincanbeconnecttoVCC.
37
GND
Ground
38,39,40
NC
Noconnection,emptypin
41
GND
Ground
42
TXD 
UARTserialdataoutput,3.3VLVTTL.
One full‐duplex asynchronous serial UART port is implemented. This UART
output is normally used for sending position, time and velocityinformation
fromthereceiverinNMEA‐0183format.Whenidle,thispinoutputHIGH.
43
RXD 
UARTserialdatainput,3.3VLVTTL.
Onefull‐duplexasynchronousserialUARTportisimplemented.ThisUARTinput
is normally for sending commands or information to the receiver in SkyTraq
binary protocol. In the idle condition, this pin should be driven HIGH. If the
drivingcircuitryis powered independentlyofPX1172R,ensurethatthis pinis
notdriventoHIGHwhenPX1172Risputtosleep,ora10K‐ohmseriesresistor
canbeaddedtominimizeleakagecurrent.
RTCM‐SC104correctiondataorbasestationSkyTraqrawmeasurement data
canalsobesenttothisUARTinput.
44
SDA
Notused,leaveunconnected
45
SCL 
Notused,leaveunconnected
46,47
NC
Noconnection,emptypin
48
GND
Ground
49
RSTN 
Externalactive‐lowresetinputtothebaseband.
Onlyneededwhenpowersupplyrisetimeisverysloworsoftwarecontrolled
resetisdesired.
50
BOOT_SEL
Noconnectionfornormaluse.Pull‐lowforloadingfirmwareintoemptyor
corruptedFlashmemoryfromROMmode.
51
TRIG
Externalinterrupttriggerinput
52
NC
Noconnection,emptypin