User's Manual

14 Firmware update

We highly recommend having the UART or JTAG accessible in any application

to have the possibility to perform a ﬁrmware update. Firmware updates can

only be performed through this interfaces once a module is implemented into

a customer PCB.

Flashing a customer or non standard ﬁrwmare makes all regulatory and con-

formity information and certiﬁcates of chapter

invalid.

14.1 Update using the UART interface

Only the UTDX, URXD and GND signals are needed for this connection. A suiting adapter/-

converter is required for a PC connection (e.g. the FTDI TTL-323R-3V3 UART to USB

converter).

None of the module pins is 5V TTL compatible. Applying overvoltage to any

pin may damage the hardware permanently. Make sure your levels are in the

range of the electrical speciﬁcation shown in chapter

14.1.1 ACC Software

As long as our standard ﬁrmware is running on the module, it can be updated with the PC

utility "AMBER Conﬁg Center" (ACC) via the serial interface. Therefore the module must be

reset while holding the BOOT pin on a high level until the bootloader is active.

If the module is not directly connected to a PC, at least the UART should be made accessi-

ble, e.g. by means of suitable connectors.

The pin BOOT must be connected to a high level (while and short after a reset) in order to

start the bootloader. If the BOOT pin is connected to GND the application will start, so for

normal operation the level on the BOOT pin must be pulled to GND (e.g. using a pull-down

with up to 1kΩ) to make sure the application is started. The reset signal shall be connectable

to GND for performing a reset of the module (e.g. using a push-button which pulls to GND

when pressed). The /RESET pin has an internal pull-up of 100 kΩ.

14.1.2 Generic UART solution

This information is not available for public and requires a NDA and Licensing procedure

for qualiﬁed customers. Additional information is available upon request from wireless-

sales@we-online.com.