uart_callback_set is returning ENSOYS error.

[Akshay]

Hi,

I’m working on enabling the asynchronous API on UART1 in the nRF Cloud Multi-Service sample for the nRF9151. Despite setting the necessary configurations, when I call uart_callback_set() for UART1, it returns -ENOSYS, which indicates that the device does not support the asynchronous API.

This is my prj.conf

#
# Copyright (c) 2022 Nordic Semiconductor ASA
#
# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
#

# Log level
# For more verbose and detailed log output, set the log level to
# CONFIG_MULTI_SERVICE_LOG_LEVEL_DBG=y instead.
CONFIG_MULTI_SERVICE_LOG_LEVEL_INF=y

# General config
CONFIG_EVENTS=y
CONFIG_PICOLIBC_IO_FLOAT=y
CONFIG_RESET_ON_FATAL_ERROR=y
CONFIG_NCS_SAMPLES_DEFAULTS=y

# LED indication
# Uncomment these to minimize LED state indication when power savings are necessary
# CONFIG_LED_VERBOSE_INDICATION=n
# CONFIG_LED_CONTINUOUS_INDICATION=n

# Or, uncomment this to completely disable LED state indication
# CONFIG_LED_INDICATION_DISABLED=y

# Improved Logging
# CONFIG_LOG_MODE_DEFERRED allows logging from multiple threads simultaneously without creating
# splintered log entries, at the cost of needing a buffer for storing logs.
CONFIG_LOG_MODE_DEFERRED=y

# CONFIG_LOG_BUFFER_SIZE is the aforementioned buffer. A size of 4096 bytes is useful for debugging
# and prototyping, but is probably more than necessary for production-ready firmware.
CONFIG_LOG_BUFFER_SIZE=4096

# Heap and stacks
# Extended AT host/monitor stack/heap sizes since some nrf_cloud credentials are longer than 1024 bytes.
CONFIG_AT_MONITOR_HEAP_SIZE=2048
CONFIG_AT_HOST_STACK_SIZE=2048
# Extended memory heap size needed both for PGPS and for encoding JSON-based nRF Cloud Device Messages.
CONFIG_HEAP_MEM_POOL_SIZE=19000
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=4096

# Enable Networking and Connection Manager.
CONFIG_NETWORKING=y
CONFIG_NET_SOCKETS=y
CONFIG_NET_SOCKETS_OFFLOAD=y
CONFIG_NET_MGMT_EVENT_STACK_SIZE=2048
CONFIG_NET_CONNECTION_MANAGER_MONITOR_STACK_SIZE=1024
CONFIG_MAIN_STACK_SIZE=2048

# Enable LTE Connectivity using Connection Manager
CONFIG_NET_IPV4=y
CONFIG_NET_IPV6=y
CONFIG_NET_IPV6_NBR_CACHE=n
CONFIG_NET_IPV6_MLD=n
CONFIG_NET_CONNECTION_MANAGER=y
CONFIG_NRF_MODEM_LIB_NET_IF=y
CONFIG_NRF_MODEM_LIB_NET_IF_AUTO_DOWN=y
CONFIG_NRF_MODEM_LIB_NET_IF_DOWN_DEFAULT_LTE_DISCONNECT=y

# Enable power savings mode
CONFIG_LTE_PSM_REQ=y
# Set the PSM Requested Active Time to 20 seconds
CONFIG_LTE_PSM_REQ_RAT="00001010"

# Modem library
CONFIG_NRF_MODEM_LIB=y

# AT commands interface
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_AT_HOST_LIBRARY=y

# nRF Cloud
CONFIG_NRF_CLOUD_MQTT=y # This also enables FOTA by implicitly setting CONFIG_NRF_CLOUD_FOTA=y

# MQTT
CONFIG_MQTT_KEEPALIVE=120

# MCUBOOT - Needed by FOTA
CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_IMG_MANAGER=y
CONFIG_MCUBOOT_IMG_MANAGER=y
CONFIG_STREAM_FLASH_ERASE=y

# Location Services configuration
CONFIG_LOCATION=y
CONFIG_LOCATION_METHOD_GNSS=y
CONFIG_LOCATION_METHOD_CELLULAR=y
CONFIG_NRF_CLOUD_AGNSS=y
CONFIG_NRF_CLOUD_LOCATION=y
CONFIG_MODEM_INFO=y
CONFIG_MODEM_INFO_ADD_NETWORK=y
CONFIG_NRF_CLOUD_PGPS=y
CONFIG_NRF_CLOUD_PGPS_REPLACEMENT_THRESHOLD=4
CONFIG_NRF_CLOUD_PGPS_REQUEST_UPON_INIT=y

# Date Time lib - Used by PGPS and main application
CONFIG_DATE_TIME=y

# LTE link control - used by PGPS and main application
CONFIG_LTE_LINK_CONTROL=y

# Settings - used by nRF Cloud library and PGPS
CONFIG_SETTINGS=y
CONFIG_SETTINGS_FCB=y
CONFIG_FCB=y

# Download Client - used by FOTA and PGPS
CONFIG_DOWNLOAD_CLIENT=y
CONFIG_DOWNLOAD_CLIENT_HTTP_FRAG_SIZE_1024=y
CONFIG_DOWNLOAD_CLIENT_STACK_SIZE=4096
CONFIG_DOWNLOAD_CLIENT_BUF_SIZE=2300
CONFIG_DOWNLOAD_CLIENT_MAX_HOSTNAME_SIZE=128

# Flash - Used by FOTA and PGPS
CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_FLASH_MAP=y
CONFIG_STREAM_FLASH=y
CONFIG_MPU_ALLOW_FLASH_WRITE=y
CONFIG_PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY=n
CONFIG_NRF_CLOUD_ALERT=y
CONFIG_NRF_CLOUD_LOG_DIRECT=y
CONFIG_NRF_CLOUD_LOG_OUTPUT_LEVEL=3

# On initial connection to the cloud, add info sections to the shadow
CONFIG_NRF_CLOUD_SEND_DEVICE_STATUS=y
CONFIG_NRF_CLOUD_SEND_DEVICE_STATUS_NETWORK=y
CONFIG_NRF_CLOUD_SEND_DEVICE_STATUS_SIM=y
CONFIG_NRF_CLOUD_SEND_SERVICE_INFO_FOTA=y
CONFIG_NRF_CLOUD_SEND_SERVICE_INFO_UI=y

CONFIG_NRF_CLOUD_CLIENT_ID_SRC_IMEI=y
CONFIG_NRF_CLOUD_CLIENT_ID_PREFIX="nrf-"
CONFIG_NRF_CLOUD_IPV6=y # disable this for US
CONFIG_LTE_NETWORK_MODE_NBIOT_GPS=y # use LTE-M for US
CONFIG_AT_CMD_REQUESTS=n

CONFIG_TFM_SECURE_UART=n
CONFIG_TFM_LOG_LEVEL_SILENCE=y
CONFIG_UART_USE_RUNTIME_CONFIGURE=y

CONFIG_LOCATION_TRACKING_SAMPLE_INTERVAL_SECONDS=300

CONFIG_UART_ASYNC_API=y
CONFIG_LOCATION_REQUEST_DEFAULT_TIMEOUT=60000
CONFIG_LOCATION_DATA_DETAILS=y

and this is my overlay file.

&uart1 {
	status = "okay";
};

[Øyvind]

Hello, 

Can you please provide full application logs? What version of the nRF Connect SDK are you working on?

Thanks

Kind regards,
Øyvind

[Akshay]

Hi Øyvind,

I'm using NCS 2 7.0. Unfortunately I'm not at my desk so I can't post the application log now. I saw the uart_callback_set function failing with -ENSOYS in debug.

[Akshay]

i'm using the DK, the overlay file name is nrf9151dk_nrf9151_ns.overlay and is located inside a folder called boards

[Øyvind]

Are you able to provide more details to how and where you call uart_callback_set() in the nrf_cloud_multi_service sample? What have you included in the sample in order to enable this?

[Akshay]

Hi,

This is how I'm setting up the async uart

const struct device *serialComm = DEVICE_DT_GET(DT_NODELABEL(uart1));
static uint8_t rx_buffer[RX_BUFFER_SIZE] = {0};

static void serialCommHandler(const struct device *dev, struct uart_event *evt, void *user_data)
{
    switch(evt->type){

        case UART_RX_RDY:
            if(evt->data.rx.buf[evt->data.rx.offset] == CMD_START_BYTE){

                buffer_index = 0;
            }
            data_buffer[buffer_index++] = evt->data.rx.buf[evt->data.rx.offset];

            if(data_buffer[buffer_index - 1] == CMD_END_BYTE){

                serial_packet_header_t* serial_header;
                serial_header = (serial_packet_header_t*)data_buffer;
                serialCmdParser(serial_header);
            }
        break;

        case UART_RX_DISABLED:
            uart_rx_enable(serialComm,rx_buffer,sizeof(rx_buffer),SYS_FOREVER_US);
        break;

        default:
        break;

    }
}

int serialInit(void) 
{
    int ret;

    if(!device_is_ready(serialComm)){
        return 1;
    }

    const struct uart_config uart_cfg = {
		.baudrate = 115200,
		.parity = UART_CFG_PARITY_NONE,
		.stop_bits = UART_CFG_STOP_BITS_1,
		.data_bits = UART_CFG_DATA_BITS_8,
		.flow_ctrl = UART_CFG_FLOW_CTRL_NONE
	};

    int err = uart_configure(serialComm, &uart_cfg);

	if (err == -ENOSYS) {
		return -ENOSYS;
	}


    ret = uart_callback_set(serialComm,serialCommHandler,NULL);
    if(ret){
        return 1;
    }

    ret = uart_rx_enable(serialComm,rx_buffer,sizeof(rx_buffer),SYS_FOREVER_US);
    if(ret){
        return 1;
    }

    return 0;
}

The serial_init function is then called inside the main application thread.

Since the asynchronous uart api isn't working for me, I have decided to use the interrupt driven api and that's working just fine.

[Øyvind]

Akshay said:

Since the asynchronous uart api isn't working for me, I have decided to use the interrupt driven api and that's working just fine.

Sorry, to hear that you have not been able to use this, but very happy that you found a workaround with interrupt driven API. 

That said, the serial_lte_modem uses async UART i.e. nrf/applications/serial_lte_modem/src/slm_uart_handler.c have you tried looking at this integration?

Kind regards,
Øyvind

[Akshay]

Øyvind said:

That said, the serial_lte_modem uses async UART i.e. nrf/applications/serial_lte_modem/src/slm_uart_handler.c have you tried looking at this integration?

I will check this one.

regards,