Read connectivity statistics with nrf_modem_at_scanf results in error

RE: Read connectivity statistics with nrf_modem_at_scanf results in error

Øyvind — Fri, 09 Jun 2023 06:37:53 GMT

MoritzR , I found the reason for why it fails with -77. The nrf_modem_at_scanf(cmd, fmt, ...) function needs to pass one % character in cmd, and two in fmt. Also, the "=" should be ":" in "%%XCONNSTAT=%i,%i,%i,%i,%i,%i". Here is what worked for me:

static void connstat_read(void)
{
	int err, smsrx, smstx, datarx, datatx, pmax, paver = 0;

	err = nrf_modem_at_printf("AT%%XCONNSTAT=1");
	if (err < 0) {
		printk("Failed to get system mode, error: %d\n", err);
	} else {
		printk("Result: %d\n", err);
	}
	err = nrf_modem_at_scanf("AT%XCONNSTAT?","%%XCONNSTAT: %i,%i,%i,%i,%i,%i",		
		&smstx,
		&smsrx,
		&datatx,
		&datarx,
		&pmax,
		&paver);
	if (err < 0) {
		printk("Failed to get system mode, error: %d\n", err);
	} else {
		printk("Stats: %i,%i,%i,%i,%i,%i\n",
		smstx,
		smsrx,
		datatx,
		datarx,
		pmax,
		paver);
	}
}

This will print out the following:

Result: 0
Stats: 0,0,0,0,0,0

Kind regards,
Øyvind

RE: Read connectivity statistics with nrf_modem_at_scanf results in error

Øyvind — Thu, 08 Jun 2023 20:51:27 GMT

Hi Moritz,

I was able to reproduce your last issue, I'm also seeing error code -77 (NRF_EBADMSG). There is an (outdated) blog post on DevZone which provides a guide on XCONNSTAT. Based on this, and the last comment on this blog post, I was able to print the following:

2023-06-08T20:38:26.894Z DEBUG modem << Result: 0
2023-06-08T20:38:26.970Z DEBUG modem << Connection stats: %XCONNSTAT: 0,0,0,0,0,0
2023-06-08T20:38:26.972Z DEBUG modem << OK
2023-06-08T20:38:26.974Z DEBUG modem <<  | Uptime: 20 seconds

I added the following to at_monitor sample for a quick test:

static void connstat_read(void)
{
	int err;
	char buf[50];
	err = nrf_modem_at_printf("AT%%XCONNSTAT=1");
	if (err != 0) {
		printk("Failed to get system mode, error: %d\n", err);
	} else {
		printk("Result: %d\n", err);
	}
	err = nrf_modem_at_cmd(response, sizeof(response),"AT%%XCONNSTAT?");		
	if (err != 0) {
		printk("Failed to get system mode, error: %d\n", err);
	} else {
		printk("Connection stats: %s | Uptime: %d seconds\n", response, k_uptime_get_32() / 1000);
	}
}

Let me know how that works for you.

From nrfxlib\nrf_modem\include\nrf_modem_at.h

/**
 * @brief Send a formatted AT command to the modem.
 *
 * Supports all format specifiers of printf() as implemented by the selected C library.
 * This function can return a negative value, zero or a positive value.
 *
 * @param fmt Command format.
 * @param ... Format arguments.
 *
 * @retval  0 On "OK" responses.
 * @returns A positive value On "ERROR", "+CME ERROR", and "+CMS ERROR" responses.
 *	    The type of error can be distinguished using @c nrf_modem_at_err_type.
 *	    The error value can be retrieved using @c nrf_modem_at_err.
 * @retval -NRF_EPERM The Modem library is not initialized.
 * @retval -NRF_EFAULT @c fmt is @c NULL.
 * @retval -NRF_EINVAL Bad format @c fmt.
 * @retval -NRF_ENOMEM Not enough shared memory for this request.
 * @retval -NRF_ESHUTDOWN If modem was shut down.
 */
int nrf_modem_at_printf(const char *fmt, ...);

/**
 * @brief Send an AT command to the modem and read the formatted response
 *	  into the supplied argument list.
 *
 * Supports all the format specifiers of scanf() as implemented by the selected C library.
 * This function does not support retrieving the modem response beyond reading
 * the formatted response into the argument list.
 *
 * @param cmd AT command.
 * @param fmt Response format.
 * @param ... Variable argument list.
 *
 * @returns The number of arguments matched.
 * @retval -NRF_EPERM The Modem library is not initialized.
 * @retval -NRF_EFAULT @c cmd or @c fmt are @c NULL.
 * @retval -NRF_EBADMSG No arguments were matched.
 * @retval -NRF_ENOMEM Not enough shared memory for this request.
 * @retval -NRF_ESHUTDOWN If the modem was shut down.
 */
int nrf_modem_at_scanf(const char *cmd, const char *fmt, ...);

/**
 * @brief Send a formatted AT command to the modem
 *	  and receive the response into the supplied buffer.
 *
 * @param buf Buffer to receive the response into.
 * @param len Buffer length.
 * @param fmt Command format.
 * @param ... Format arguments.
 *
 * @retval  0 On "OK" responses.
 * @returns A positive value On "ERROR", "+CME ERROR", and "+CMS ERROR" responses.
 *	    The type of error can be distinguished using @c nrf_modem_at_err_type.
 *	    The error value can be retrieved using @c nrf_modem_at_err.
 * @retval -NRF_EPERM The Modem library is not initialized.
 * @retval -NRF_EFAULT @c buf or @c fmt are @c NULL.
 * @retval -NRF_EINVAL Bad format @c fmt, or @c len is zero.
 * @retval -NRF_ENOMEM Not enough shared memory for this request.
 * @retval -NRF_E2BIG The response is larger than the supplied buffer @c buf.
 * @retval -NRF_ESHUTDOWN If the modem was shut down.
 */
int nrf_modem_at_cmd(void *buf, size_t len, const char *fmt, ...);

Kind regards,
Øyvind

RE: Read connectivity statistics with nrf_modem_at_scanf results in error

MoritzR — Tue, 06 Jun 2023 12:56:08 GMT

Hello Oyvind,

yes, CONFIG_NRF_MODEM_LIB=y is included.

Modem firmware version is 1.3.4.

I adopted the following from the given example:

int smsrx, smstx, datarx, datatx, pmax, paver = 0;
	int ret = nrf_modem_at_scanf("AT%%XCONNSTAT?","%%XCONNSTAT=%i,%i,%i,%i,%i,%i",		
		&smstx,
		&smsrx,
		&datatx,
		&datarx,
		&pmax,
		&paver);
	printk("Ret: %i\n",ret);
	printk("Stats: %i,%i,%i,%i,%i,%i\n",
		smstx,
		smsrx,
		datatx,
		datarx,
		pmax,
		paver);

And it returns error code -77 (NRF_EBADMSG No arguments were matched) But it should be alright as the example message in the documentation is "%XCONNSTAT=2,3,45,60,708,650".

I must be missing something...

Thanks for your help

Kind regards, Moritz

RE: Read connectivity statistics with nrf_modem_at_scanf results in error

Øyvind — Tue, 30 May 2023 18:27:37 GMT

Hello Maritz,

Have you done as the error states? In you prj.conf have you added CONFIG_NRF_MODEM_LIB?

Are you using one of our samples as a starting point? Have you looked at our nRF9160:AT Monitor sample? The AT monitor sample demonstrates how to use the AT monitor library and define AT monitors to receive AT notifications from the Modem library.

Kind regards,
Øyvind