LP-UART sample crashes continuously

RE: LP-UART sample crashes continuously

Simon — Thu, 06 May 2021 13:55:04 GMT

Please create a new DevZone ticket

RE: LP-UART sample crashes continuously

Hamada888 — Thu, 06 May 2021 12:46:08 GMT

hei
Can you help me to make the UART transmitioin goes only once?

RE: LP-UART sample crashes continuously

Simon — Mon, 29 Mar 2021 12:12:23 GMT

I was able to make "interrupt driven" mode work using NCS v1.5.0 and nrf52840dk_nrf52840 and the following changes:

diff --git a/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay b/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
index 54d3d0bc1..266936e12 100644
--- a/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
+++ b/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
@@ -15,6 +15,6 @@
        };
 };

-&uart0 {
+/*&uart0 {
        status = "disabled";
-};
+};*/
diff --git a/samples/peripheral/lpuart/diffs.patch b/samples/peripheral/lpuart/diffs.patch
new file mode 100644
index 000000000..e69de29bb
diff --git a/samples/peripheral/lpuart/prj.conf b/samples/peripheral/lpuart/prj.conf
index ba5f898e0..4f1e856dd 100644
--- a/samples/peripheral/lpuart/prj.conf
+++ b/samples/peripheral/lpuart/prj.conf
@@ -11,13 +11,13 @@ CONFIG_NRF_SW_LPUART=y
 # in overlay.

 # CONFIG_USE_SEGGER_RTT=n
-# CONFIG_LOG=y
+CONFIG_LOG=y
 # CONFIG_NO_OPTIMIZATIONS=y
 # CONFIG_ASSERT=y

 # Comment this section for debugging
-CONFIG_CONSOLE=n
-CONFIG_UART_CONSOLE=n
+#CONFIG_CONSOLE=n
+#CONFIG_UART_CONSOLE=n

 # Uncomment to use lpuart using interrupt driven API
-# CONFIG_NRF_SW_LPUART_INT_DRIVEN=y
+CONFIG_NRF_SW_LPUART_INT_DRIVEN=y

I then got the following output in Termite:

*** Booting Zephyr OS build v2.4.99-ncs1  ***
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes
read 1 bytes
read 5 bytes

Could you test this on your end and see if you're able to make it work?

RE: LP-UART sample crashes continuously

Anirudh Agarkhed — Mon, 22 Mar 2021 14:02:06 GMT

That config seems to work fine, when I apply the patches - Patch 1 and Patch 2. Changing the prj.conf by itself does not make this work.

With the patch applied, LP-UART works when "async" mode is used.

When configuration is changed to "Interrupt Driven" mode, MPU fault is observed. Following configuration changes were made -

In prj.conf enabled - CONFIG_NRF_SW_LPUART_INT_DRIVEN=y

In board specific config -

CONFIG_UART_1_ASYNC=n
CONFIG_UART_1_INTERRUPT_DRIVEN=y

Changing these configurations results in continuous crash due to "MPU Fault - Data Access Violation"

Which configurations are to be modified to change to "interrupt driven" mode?

RE: LP-UART sample crashes continuously

Simon — Mon, 08 Mar 2021 12:49:37 GMT

I was not able to reproduce the MPU fault. Can you test with the same changes I did:

diff --git a/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay b/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
index 54d3d0bc1..d3ad94ce1 100644
--- a/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
+++ b/samples/peripheral/lpuart/boards/nrf52840dk_nrf52840.overlay
@@ -1,8 +1,8 @@
 /* SPDX-License-Identifier: LicenseRef-Nordic-5-Clause */

 &uart1 {
-       rx-pin = <44>;
-       tx-pin = <45>;
+       rx-pin = <44>; // 12
+       tx-pin = <45>; // 13
        /delete-property/ rts-pin;
        /delete-property/ cts-pin;

@@ -10,11 +10,11 @@
                compatible = "nordic,nrf-sw-lpuart";
                status = "okay";
                label = "LPUART";
-               req-pin = <46>;
-               rdy-pin = <47>;
+               req-pin = <46>; // 14
+               rdy-pin = <47>; // 15
        };
 };

-&uart0 {
+/*&uart0 {
        status = "disabled";
-};
+};*/
diff --git a/samples/peripheral/lpuart/prj.conf b/samples/peripheral/lpuart/prj.conf
index ba5f898e0..6c0eaf00c 100644
--- a/samples/peripheral/lpuart/prj.conf
+++ b/samples/peripheral/lpuart/prj.conf
@@ -11,13 +11,13 @@ CONFIG_NRF_SW_LPUART=y
 # in overlay.

 # CONFIG_USE_SEGGER_RTT=n
-# CONFIG_LOG=y
+CONFIG_LOG=y
 # CONFIG_NO_OPTIMIZATIONS=y
 # CONFIG_ASSERT=y

 # Comment this section for debugging
-CONFIG_CONSOLE=n
-CONFIG_UART_CONSOLE=n
+#CONFIG_CONSOLE=n
+#CONFIG_UART_CONSOLE=n

 # Uncomment to use lpuart using interrupt driven API
 # CONFIG_NRF_SW_LPUART_INT_DRIVEN=y

Best regards,

Simon