Datasheet

 2015 Microchip Technology Inc. DS50002279B-page 5
RN4020
15 WAKE_HW
Hardware wake from Dormant state. Setting the
WAKE_HW (pin15) high wakes the module from Dor-
mant mode. During the module power up, if
WAKE_HW pin is flipped high and low for three
cycles (putting the WAKE_HW pin into high, low, and
then high again is considered as one flip cycle) in the
first five seconds, then the module performs a factory
Reset. If the WAKE_SW pin is high when a factory
Reset is performed, the factory Reset is a full reset.
Otherwise, it is a partial reset that retains the device
name, private service and scripts. Set WAKE_HW
pin to low in order to lower power consumption in
Deep Sleep and Dormant modes.
Active-high; internal pull down
16 GND Ground Ground
17 SPI/PIO
SPI/PIO for pins 10-13; active-high
Input with internal pull down;
selects SPI on pins 10-13
18
RTS
PIO[6]
Reserved for RTS if hardware flow control on UART
is enabled. If the data transmission to RN4020 must
be halted, assert RTS to high. RTS pin operates
independently from the CTS (pin 14).
• RTS (output)
• PIO[6]
19
PWM4
PIO[7]
Spare PIO
PIO[7]; Spare PIO configurable as
input or output
20 RSVD Do not connect. Factory diagnostics. No Connect
21 SDA
SDA Data line of the I
2
C interface. The RN4020
always acts as the I
2
C Master.
SDA
22 SCL I
2
C Clock SCL
23 VDD Supply voltage 1.8 to 3.6V
24 GND Ground Ground
TABLE 1-1: PIN DESCRIPTION (CONTINUED)
Pin Name Description Function
CAUTION
A full factory Reset erases scripts and sets the
device name to the serialized name. For more
information, refer to the SF Command in the
RN4020 Bluetooth Low Energy User's Guide
(DS70005191).