5 I/O pins
5.1 PPS (pin 4)
PPS is the time pulse every one second. It can be configured with different condition of pulses.
For firsts PCB, it is recommended to plan to have some filtering components on Teseo-LIV4F/FM PPS (pin 4).
5.2 EXTINT (pin 5)
It is a GPIO which, by default, is a trigger pin to external interrupt.
Leave it floating if not used.
5.3 RESETn (pin 9)
It can force a Teseo-LIV4F/FM under reset.
Reset signal is active low.
Host processor must have full control of this pin to guarantee the Teseo-LIV4F/FM’s firmware upgrade support.
Do not use pull-up or pull-down when connecting to MCU.
5.3.1 Reset minimum timing
Table 1. Reset minimum timing
Parameter Symbol Pin Condition Min. Typ. Max Unit
Reset input time tRSTL RESETn There is power supply and the oscillator is stable 100 - - mS
Figure 4. Reset (RESETn pin) minimum timing
5.4 RF_IN (pin 10)
It is the RF input.
DC (equals to VCC voltage) is present Teseo-LIV4F/FM version.
5.5 PRTRG (pin 18)
Keep PRTRG pin floating during system power-up or the external reset (RESETn from low to high), and the
module will enter User Normal Mode.
It’s a programming pin used to program the module in production line.
Leave PRTRG pin floating.
UM3004
I/O pins
UM3004 - Rev 3 page 7/17
