BL654 UART question

[Bob Faist]

Looking for advice on reading data from the BL654 UART RX pin which is getting a text data stream from an STM32 micro. 

I tried the "peripheral_uart" sample app in Segger Studio but it crashes a lot and sometimes I see UART events but have not seen any actual data yet.

Should I use UART IRQ API?  Or UART FIFO API? Should I be using the Nordic UART system CONFIG_BT_NUS like the peripheral_uart example?

I have verified data is working using a terminal to read the serial port.  I have verified the pin assignments and baud rate for the zephyr board DTS file.

Thanks.

[JONATHAN LL]

Hi,

Could you share logs of what happens when it crashes?

What type of custom board is it ? Are you sure that you have correct overlay/board file?

Regards,
Jonathan

[Bob Faist]

*** Booting Zephyr OS build v2.6.0-rc1-ncs1  ***
[00:00:02.292,755] <inf> peripheral_uart: UART_RX_BUF_REQUEST
[00:00:02.298,583] <inf> fs_nvs: 8 Sectors of 4096 bytes
[00:00:02.298,583] <inf> fs_nvs: alloc wra: 7, f90
[00:00:02.298,583] <inf> fs_nvs: data wra: 7, d8
[00:00:02.298,706] <inf> sdc_hci_driver: SoftDevice Controller build revision: 
                                         58 5d 8b 31 54 67 00 e9  b8 4a a7 df a9 9c e4 1c |X].1Tg.. .J......
                                         b3 0b ce 74                                      |...t             
[00:00:02.302,459] <inf> bt_hci_core: No ID address. App must call settings_load()
[00:00:02.302,459] <inf> peripheral_uart: Bluetooth initialized
[00:00:02.314,849] <inf> peripheral_uart: Starting Nordic UART service example

[00:00:02.314,880] <inf> peripheral_uart: ble_write_thread after ble_init_ok
[00:00:18.957,458] <inf> peripheral_uart: UART_RX_BUF_RELEASED
[00:00:18.957,458] <inf> peripheral_uart: UART_RX_BUF_REQUEST

Above is the log.  It crashes with at "z_arm_usage_fault".  

The custom board is a BL654 and STM32 reading data from temperature and gyroscope sensors.

Just prototype stage.  I copied the "bl654_dvk" board DTS file and modified for our custom board.

Some of the DTS fiie:

chosen {
 zephyr,console = &uart0;
 zephyr,shell-uart = &uart0;
 zephyr,uart-mcumgr = &uart0;
 zephyr,bt-mon-uart = &uart0;
 zephyr,bt-c2h-uart = &uart0;
 zephyr,sram = &sram0;
 zephyr,flash = &flash0;
 zephyr,code-partition = &slot0_partition;
 };

&uart0 {
 compatible = "nordic,nrf-uarte";
 current-speed = <115200>;
 status = "okay";
 tx-pin = <6>;
 rx-pin = <8>;
 rts-pin = <5>;
 cts-pin = <7>;
};

[JONATHAN LL]

Hi,

peripheral_uart example should suffice, and it looks correct to my understanding of how you have set it up. So i am curious how the STM32 micro is configured, does it have flow controlled? how is it connected? Do you have schematics of how they interface?

I don's see anything of concern in the setup so it leads me to think that there is something with the interface to the STM32 or how it is configured. 

Regards,
Jonathan

[Bob Faist]

I use the Mac app "CoolTerm" to read the serial port which returns data like this:

pos: 168 1 255
temp: 75.53 F

CTS/DTR/XON flow control are all turned off in CoolTerm.

I can check with the STM32 developer and see about the flow control.