Tool/software:
Hello expert,
Can CC2340R5 support 4 wire UART for the bootloader function?
I found the following sentence in RTM but would like to confirm.
8.5.1 ROM Serial Bootloader Interfaces
The bootloader communicates with an external device over a 2-pin UART or a 4-pin SPI interface. The
communication protocol and transport layers are described in the following subsections.
Regards,
A.Fujinaka
Hello A. Fujinaka,
From what I can read from the TRM and internally the Serial bootloader with UART only uses two UART pins (one UART_RX and one UART_RX):
See the table below of the available UART configurations:
How to select between UART or SPI:
UART Auto baud sequence:
Hello Alex,
After some communication with my customer, they understand CC2340R5 does not support 4 wire UART on ROM bootloader.
Next question[
1. If they will use User bootloader function , they can configure UART as 4 wire ?
2. If they will SPI as ROM bootloader , and use UART for the MCU I/F, they can use 4 wire UART to connect to MCU I/F?
Regards,
A.Fujinaka
Hello Fujinaka-san,
1. I have asked RnD, this it is not clear to me in the TRM if the user defined bootloader uses the same requirements (2 wire UART) or not.
2. So to understand the question, the customer will use SPI with the Serial Bootloader, then once the application takes over they will use 4 wire UART in the application? (in sysconfig if you use the hardware UART it defaults to 2 wire UART but if you set use hardware to use none it allows the flow control to be selected which then allows for 4 wire UART).
Thanks,
Alex F
Hello Alex,
1. Yes, please provide answer from RnD.
2. Your understanding is correct.
Regards,
A.Fujinaka
Hello Fujinaka-san,
1. RnD responded, the customer can you any configuration they like with the user bootloader (so in this example they can use 4 wire UART), however the user bootloader is ultimately dependent on how the customer codes and configures it.
2. This is not an issue and is currently possible.