User's Manual

while user self-defined private UUID must be in long form. For the details of
Bluetooth SIG adopted services and characteristics, please refer to
https://developer.bluetooth.org/gatt/profiles/Pages/ProfilesHome.aspx.
The accessibility of each characteristic is defined by 8-bit characteristic property in
bitmap format, as shown in table 1.
Table 1. Characteristic Properties
Property
Bitmap
Description
Extended
Property *
0b10000000
Additional property available
Authenticated
Write *
0b01000000
Write characteristic with authentication from client
to server
Indicate
0b00100000
Indicate value of characteristic with
acknowledgement from server to client
Notify
0b00010000
Notify value of characteristic without
acknowledgement from server to client
Write
0b00001000
Write value of characteristic with acknowledgement
from client to server
Write without
response
0b00000100
Write value of characteristic without
acknowledgment from client to server
Read
0b00000010
Read value of characteristic. Value is sent from
server to client
Broadcast
0b00000001
Broadcast value of characteristic
* Currently not supported in RN4020
3. Microchip RN4020 OEM Module Control Interface
Microchip RN4020 module is fully agent certified Bluetooth Low Energy single
mode OEM module. User controls the module through GPIO lines and UART
interface.
3.1 RN4020 GPIO Control Lines
RN4020 uses 3 input GPIOs to set the module in different states and 3 output GPIOs
to indicate current status.
GPIO 3 is used to control the operating state of RN4020. When GPIO 3 is put to high,
the module wakes up and is set into active mode. Once waking up, “CMD” will be
output to the UART and indicate that module is in command mode and ready to take
commands from UART.
On the other hand, when GPIO 3 is set to be low, the module will exit command
mode by output “END” to UART and then operates in deep sleep mode. UART