samples: protocols_serialization: use different GPIO pins of UART

Damian-Nordic · rlubos · commit 6b28fe65afe5 · 2024-11-18T20:02:57.000+01:00
One of the previously selected pins for uart21 peripheral
was also used to drive LED 1 on nRF54L15 DK, which might
have interferred with the UART hardware flow control.

Due to lack of available pins on GPIO port 1, use the pins
dedicated to Button 1 &amp; 2 but make sure that the buttons
are removed from the devicetree to prevent from using them
accidentally.

Also, fix pull-up configuration for UART pins.

Signed-off-by: Damian Krolik &lt;damian.krolik@nordicsemi.no&gt;
diff --git a/CODEOWNERS b/CODEOWNERS
@@ -274,7 +274,7 @@
 
 /doc/**/*.svg                             @nrfconnect/ncs-doc-leads
 /doc/**/*.png                             @nrfconnect/ncs-doc-leads
-
+/doc/**/*.webp                            @nrfconnect/ncs-doc-leads
 
 # Drivers
 /drivers/bluetooth/                       @nrfconnect/ncs-co-drivers @nrfconnect/ncs-dragoon
diff --git a/doc/nrf/images/ps_nrf54l_connections.png b/doc/nrf/images/ps_nrf54l_connections.png
diff --git a/doc/nrf/images/ps_nrf54l_connections.webp b/doc/nrf/images/ps_nrf54l_connections.webp
diff --git a/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst b/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst
@@ -350,7 +350,8 @@ PMIC samples
 Protocol serialization samples
 ------------------------------
 
-|no_changes_yet_note|
+* Updated GPIO pins on nRF54L15 DK used for communication between the client and server over UART.
+  One of the previously selected pins was also used to drive an LED, which may have disrupted the UART communication.
 
 SDFW samples
 ------------
diff --git a/samples/nrf_rpc/protocols_serialization/client/README.rst b/samples/nrf_rpc/protocols_serialization/client/README.rst
@@ -65,6 +65,10 @@ Testing
 
 To test the client sample, follow the instructions in the :ref:`protocols_serialization_server_sample_testing` section of the protocol serialization server sample test procedure.
 
+.. note::
+   When using the nRF54L15 DK, do not press **Button 1** or **Button 2**.
+   The GPIO pins connected to these buttons are used by the UART peripheral for communication with the server device.
+
 Dependencies
 ************
 
diff --git a/samples/nrf_rpc/protocols_serialization/client/boards/nrf52840dk_nrf52840.overlay b/samples/nrf_rpc/protocols_serialization/client/boards/nrf52840dk_nrf52840.overlay
@@ -17,14 +17,14 @@
 
 &uart1_default {
 	group1 {
-		psels = <NRF_PSEL(UART_RX, 1, 1)>,
-			<NRF_PSEL(UART_RTS, 1, 3)>;
-		bias-pull-up;
-	};
-	group2 {
 		psels = <NRF_PSEL(UART_TX, 1, 2)>,
+			<NRF_PSEL(UART_RTS, 1, 3)>,
 			<NRF_PSEL(UART_CTS, 1, 4)>;
 	};
+	group2 {
+		psels = <NRF_PSEL(UART_RX, 1, 1)>;
+		bias-pull-up;
+	};
 };
 
 &uart1_sleep {
diff --git a/samples/nrf_rpc/protocols_serialization/client/boards/nrf54l15dk_nrf54l15_cpuapp.overlay b/samples/nrf_rpc/protocols_serialization/client/boards/nrf54l15dk_nrf54l15_cpuapp.overlay
@@ -7,28 +7,38 @@
 	chosen {
 		nordic,rpc-uart = &uart21;
 	};
+
+	/* delete all buttons except button0 to free GPIO pins assigned to uart21 below */
+	buttons {
+		/delete-node/ button1;
+		/delete-node/ button2;
+		/delete-node/ button3;
+	};
 };
 
 &pinctrl {
 	uart21_default: uart21_default {
 		group1 {
-			psels = <NRF_PSEL(UART_TX, 1, 11)>,
-				<NRF_PSEL(UART_RX, 1, 10)>,
-				<NRF_PSEL(UART_RTS, 1, 12)>,
-				<NRF_PSEL(UART_CTS, 1, 13)>;
+			psels = <NRF_PSEL(UART_TX, 1, 8)>,
+				<NRF_PSEL(UART_RTS, 1, 11)>,
+				<NRF_PSEL(UART_CTS, 1, 12)>;
+		};
+		group2 {
+
+			psels = <NRF_PSEL(UART_RX, 1, 9)>;
+			bias-pull-up;
 		};
 	};
 
 	uart21_sleep: uart21_sleep {
 		group1 {
-			psels = <NRF_PSEL(UART_TX, 1, 11)>,
-				<NRF_PSEL(UART_RX, 1, 10)>,
-				<NRF_PSEL(UART_RTS, 1, 12)>,
-				<NRF_PSEL(UART_CTS, 1, 13)>;
+			psels = <NRF_PSEL(UART_TX, 1, 8)>,
+				<NRF_PSEL(UART_RX, 1, 9)>,
+				<NRF_PSEL(UART_RTS, 1, 11)>,
+				<NRF_PSEL(UART_CTS, 1, 12)>;
 			low-power-enable;
 		};
 	};
-
 };
 
 &uart21 {
diff --git a/samples/nrf_rpc/protocols_serialization/server/Kconfig b/samples/nrf_rpc/protocols_serialization/server/Kconfig
@@ -38,6 +38,7 @@ endif
 
 config NRF_PS_SERVER_FATAL_ERROR_TRIGGER
 	bool "Fatal error trigger"
+	select DK_LIBRARY
 	help
 	  Enables triggering a fatal error by pressing Button 1 on the development
 	  kit. This trigger allows for testing the feature of logging over RPC that
diff --git a/samples/nrf_rpc/protocols_serialization/server/README.rst b/samples/nrf_rpc/protocols_serialization/server/README.rst
@@ -52,15 +52,19 @@ User interface
 **************
 
 .. tabs::
+
    .. group-tab:: nRF52840 DK
 
-      Button 4:
+      Button 1:
+
          * When the ``log_rpc`` snippet is enabled: triggers a fatal error.
-            This is used for testing the crash log feature.
+           This is used for testing the crash log feature.
          * Otherwise: not available.
 
    .. group-tab:: nRF54L15 DK
-      Button 3:
+
+      Button 0:
+
          * When the ``log_rpc`` snippet is enabled: triggers a fatal error.
            This is used for testing the crash log feature.
          * Otherwise: not available.
@@ -81,6 +85,10 @@ Testing
 
 After building the Protocols serialization server sample and programming it to your development kit, connect it to a second device running the :ref:`Protocol serialization client <nrf_rpc_protocols_serialization_client>` sample to test either the Bluetooth LE, OpenThread or NFC functionality.
 
+.. note::
+   When using the nRF54L15 DK, do not press **Button 1** or **Button 2**.
+   The GPIO pins connected to these buttons are used by the UART peripheral for communication with the client device.
+
 .. _protocols_serialization_server_app_connection:
 
 Connecting the client and server samples
@@ -137,17 +145,17 @@ In the protocols serialization samples, one peripheral is used for shell and log
            * - Server
              - Client
              - Function on server
-           * - **P1.10**
-             - **P1.11**
-             - RX
-           * - **P1.11**
-             - **P1.10**
+           * - **P1.8**
+             - **P1.9**
              - TX
-           * - **P1.12**
-             - **P1.13**
-             - RTS (hardware flow control)
-           * - **P1.13**
+           * - **P1.9**
+             - **P1.8**
+             - TX
+           * - **P1.11**
              - **P1.12**
+             - RTS (hardware flow control)
+           * - **P1.12**
+             - **P1.11**
              - CTS (hardware flow control)
            * - **GND**
              - **GND**
@@ -156,7 +164,7 @@ In the protocols serialization samples, one peripheral is used for shell and log
         To enable the communication between the client and the server devices, connect the pins on the two nRF54L15 DKs using jumper wires.
         The following illustration demonstrates the pin connections:
 
-        .. figure:: /images/ps_nrf54l_connections.png
+        .. figure:: /images/ps_nrf54l_connections.webp
             :alt: nRF54L15 DK server and client pin connections
 
 Testing Bluetooth LE API serialization
diff --git a/samples/nrf_rpc/protocols_serialization/server/boards/nrf52840dk_nrf52840.overlay b/samples/nrf_rpc/protocols_serialization/server/boards/nrf52840dk_nrf52840.overlay
@@ -17,14 +17,14 @@
 
 &uart1_default {
 	group1 {
-		psels = <NRF_PSEL(UART_RX, 1, 1)>,
-			<NRF_PSEL(UART_RTS, 1, 3)>;
-		bias-pull-up;
-	};
-	group2 {
 		psels = <NRF_PSEL(UART_TX, 1, 2)>,
+			<NRF_PSEL(UART_RTS, 1, 3)>,
 			<NRF_PSEL(UART_CTS, 1, 4)>;
 	};
+	group2 {
+		psels = <NRF_PSEL(UART_RX, 1, 1)>;
+		bias-pull-up;
+	};
 };
 
 &uart1_sleep {
diff --git a/samples/nrf_rpc/protocols_serialization/server/boards/nrf54l15dk_nrf54l15_cpuapp.overlay b/samples/nrf_rpc/protocols_serialization/server/boards/nrf54l15dk_nrf54l15_cpuapp.overlay
@@ -7,28 +7,38 @@
 	chosen {
 		nordic,rpc-uart = &uart21;
 	};
+
+	/* delete all buttons except button0 to free GPIO pins assigned to uart21 below */
+	buttons {
+		/delete-node/ button1;
+		/delete-node/ button2;
+		/delete-node/ button3;
+	};
 };
 
 &pinctrl {
 	uart21_default: uart21_default {
 		group1 {
-			psels = <NRF_PSEL(UART_TX, 1, 11)>,
-				<NRF_PSEL(UART_RX, 1, 10)>,
-				<NRF_PSEL(UART_RTS, 1, 12)>,
-				<NRF_PSEL(UART_CTS, 1, 13)>;
+			psels = <NRF_PSEL(UART_TX, 1, 8)>,
+				<NRF_PSEL(UART_RTS, 1, 11)>,
+				<NRF_PSEL(UART_CTS, 1, 12)>;
+		};
+		group2 {
+
+			psels = <NRF_PSEL(UART_RX, 1, 9)>;
+			bias-pull-up;
 		};
 	};
 
 	uart21_sleep: uart21_sleep {
 		group1 {
-			psels = <NRF_PSEL(UART_TX, 1, 11)>,
-				<NRF_PSEL(UART_RX, 1, 10)>,
-				<NRF_PSEL(UART_RTS, 1, 12)>,
-				<NRF_PSEL(UART_CTS, 1, 13)>;
+			psels = <NRF_PSEL(UART_TX, 1, 8)>,
+				<NRF_PSEL(UART_RX, 1, 9)>,
+				<NRF_PSEL(UART_RTS, 1, 11)>,
+				<NRF_PSEL(UART_CTS, 1, 12)>;
 			low-power-enable;
 		};
 	};
-
 };
 
 &uart21 {
diff --git a/samples/nrf_rpc/protocols_serialization/server/snippets/openthread/boards/nrf54l15dk_nrf54l15_cpuapp.overlay b/samples/nrf_rpc/protocols_serialization/server/snippets/openthread/boards/nrf54l15dk_nrf54l15_cpuapp.overlay
@@ -10,9 +10,6 @@
 			     <&gpio1 10 GPIO_ACTIVE_HIGH>,		    // LED 1
 			     <&gpio2 7 GPIO_ACTIVE_HIGH>,		    // LED 2
 			     <&gpio1 14 GPIO_ACTIVE_HIGH>,		    // LED 3
-			     <&gpio1 13 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,  // Button 0
-			     <&gpio1 9 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,   // Button 1
-			     <&gpio1 8 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,   // Button 2
-			     <&gpio0 4 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;   // Button 3
+			     <&gpio1 13 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;  // Button 0
 	};
 };
diff --git a/samples/nrf_rpc/protocols_serialization/server/src/fatal_error_trigger.c b/samples/nrf_rpc/protocols_serialization/server/src/fatal_error_trigger.c
@@ -4,58 +4,26 @@
  * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
  */
 
+#include <dk_buttons_and_leds.h>
+
 #include <zephyr/init.h>
 #include <zephyr/kernel.h>
-#include <zephyr/drivers/gpio.h>
-#include <zephyr/sys/util.h>
 #include <zephyr/logging/log.h>
 
 LOG_MODULE_DECLARE(nrf_ps_server, CONFIG_NRF_PS_SERVER_LOG_LEVEL);
 
-/*
- * This module intentionally do not use DK library.
- * On nRF54l15 default buttons overlap with UART pins configuration.
- */
-
-#define SW0_NODE DT_ALIAS(sw3)
-
-static const struct gpio_dt_spec button = GPIO_DT_SPEC_GET_OR(SW0_NODE, gpios, {0});
-static struct gpio_callback button_cb_data;
-
-void button_pressed(const struct device *dev, struct gpio_callback *cb, uint32_t pins)
+static void button_handler(uint32_t button_state, uint32_t has_changed)
 {
-	LOG_ERR("Button causing k_oops pressed.\n");
-	k_oops();
+	LOG_ERR("Fatal error button pressed - triggering k_oops");
+
+	if (button_state & DK_BTN1_MSK) {
+		k_oops();
+	}
 }
 
 static int button_handler_init(void)
 {
-	int ret;
-
-	if (!gpio_is_ready_dt(&button)) {
-		LOG_DBG("Error: button device %s is not ready\n", button.port->name);
-		return 0;
-	}
-
-	ret = gpio_pin_configure_dt(&button, GPIO_INPUT);
-	if (ret != 0) {
-		LOG_DBG("Error %d: failed to configure %s pin %d\n", ret, button.port->name,
-			button.pin);
-		return 0;
-	}
-
-	ret = gpio_pin_interrupt_configure_dt(&button, GPIO_INT_EDGE_TO_ACTIVE);
-	if (ret != 0) {
-		LOG_DBG("Error %d: failed to configure interrupt on %s pin %d\n", ret,
-			button.port->name, button.pin);
-		return 0;
-	}
-
-	gpio_init_callback(&button_cb_data, button_pressed, BIT(button.pin));
-	gpio_add_callback(button.port, &button_cb_data);
-	LOG_DBG("Set up button at %s pin %d\n", button.port->name, button.pin);
-
-	return 0;
+	return dk_buttons_init(button_handler);
 }
 
 SYS_INIT(button_handler_init, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY);
