How to receive SMS message in standby mode in nRF9160?

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Mon, 16 Sep 2019 08:43:24 GMT

Great to hear that you solved it 🙂

Kind regards

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Sat, 14 Sep 2019 04:56:41 GMT

I solved this issue!

You must need to use the same file descriptor when running "AT+CNMI=3,2,0,1", "AT+CNMI?" and "AT+CNMA". Get a fd by this line and, and send the above commands with this.

int at_socket_fd = socket(AF_LTE, 0, NPROTO_AT);

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Fri, 13 Sep 2019 09:26:51 GMT

If you set a handler via this function call:

https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/drivers/at_cmd/at_cmd.c#L312

Then you should get subscribed indication/events from the modem, such as sms.

Could you try this and see if that works better?

Kind regards,

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 11 Sep 2019 15:00:59 GMT

I'm searching a way of polling SMS receiving notification, but I found only mqtt_simple sample program which has mqtt-specific polling function.

How can I poll SMS receiving notification? Do you know any reference?

I used blocking_recv function which I found in simple_at and this doesn't work.

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 11 Sep 2019 14:27:26 GMT

Hi, Hakon. Thank you for your reply!

So these steps should be correct

1. run "AT+CNMI=3,2,0,1"
2. polling for an incoming SMS
3. send SMS from a server
4. SMS notification shows up once the SMS is received
5. run "AT+CNMA" right after the notification
*If I don't run "AT+CNMA" when SMS is received, SMS notification is disabled.

OK, I got this.

However, when I don't comment out at_cmd_set_notification_handler(), no SMS receiving notification shows up, so MCU doesn't know the timing of sending "AT+CNMA" command. I guess at_cmd_set_notification_handler() needs some fix.

I will try to find a way of polling an incoming SMS.

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Wed, 11 Sep 2019 13:42:22 GMT

Hi,

I am sorry for the late reply.

When registering a request from AT+CNMI, you should use AT+CNMA to ACK the received message.

If the ACK is not delivered before the timeout, the CNMI is released, as per this specification:

https://infocenter.nordicsemi.com/topic/ref_at_commands/REF/at_commands/text_mode/cnma_set.html?cp=2_1_8_5_0

I do not see how commenting out the at_cmd_set_notification_handler() should influence this procedure. Could you see if the same behavior is observed if you ACK the SMS using CNMA?

Kind regards,

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 11 Sep 2019 08:10:55 GMT

I'm pretty sure that "at_cmd_set_notification_handler" causes this issue.

When I comment out the two lines, SMS notification shows up, but when I don't, it doesn't show up.

Could you help me fix this issue?

Thank you so much for helping me a lot!

<lte_lc.c>

static int w_lte_lc_init_and_connect(struct device *unused)
{
.
.
.
	if (at_cmd_write(network_mode, NULL, 0, NULL) != 0) {
		return -EIO;
	}

	k_sem_init(&link, 0, 1);

//	at_cmd_set_notification_handler(at_handler);

	if (at_cmd_write(normal, NULL, 0, NULL) != 0) {
		return -EIO;
	}

	k_sem_take(&link, K_FOREVER);

//	at_cmd_set_notification_handler(NULL);

	return 0;
}

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Sun, 08 Sep 2019 11:12:43 GMT

Hi, Hakon.

I managed to receive SMS during eDRX on at_client and LTE Link Monitor.

AT+CFUN=4
AT%XBANDLOCK=1,"10000000" // Some carriers don't support SMS during eDRX
AT+CEDRXS=2,4,"0110" // enable eDRX
AT%XPTW=4,"0111"
AT+CNMI=3,2,0,1
AT%XSYSTEMMODE=1,0,0,0
AT+CFUN=1
Wait for a while
AT+CFUN? // Make sure LTE conection is established
AT+CEDRXRDP
AT+CNMI?
SMS from server
wait until unsolicited message shows up on LLM

When I implement this code in usual project and check if SMS notification shows up on LTE Link Monitor, I can't receive SMS notification even though I set "AT+CNMI=3,2,0,1." SMS seems to be received, but SMS notification is not generated.

<main>
.
.
.
void send_at_commands(void)
{

    char recv_buf[1024 + 1];
	const char *at_commands[] = { "AT+CEDRXRDP", "AT+CNMI?" };

	int at_socket_fd = socket(AF_LTE, 0, NPROTO_AT);

	if (at_socket_fd < 0) {
		printk("Socket err: %d, errno: %d\r\n", at_socket_fd, errno);
	}
	for (int i = 0; i < ARRAY_SIZE(at_commands); i++) {
        printk("%s\n", at_commands[i]);
		int bytes_written = send(at_socket_fd, at_commands[i],
					 strlen(at_commands[i]), 0);
		if (bytes_written > 0) {
			int r_bytes = blocking_recv(at_socket_fd, recv_buf, sizeof(recv_buf), MSG_DONTWAIT);
			if (r_bytes > 0) {
				printk("%s", recv_buf);
			}
		}
	}
	printk("Closing socket\n\r");
	(void)close(at_socket_fd);
}

void main(void)
{
	printk("The AT client program started\n");
	modem_configure();
    send_at_commands();
}

<lte_lc.c>
.
.
#if defined(CONFIG_LTE_LOCK_BANDS)
/* Lock LTE bands 8 (volatile setting) */
static const char lock_bands[] = "AT%XBANDLOCK=2,\"10000000\"";
#endif
/* Request eDRX settings to be used */
static const char edrx_req[] = "AT+CEDRXS=1,"CONFIG_LTE_EDRX_REQ_ACTT_TYPE",\""CONFIG_LTE_EDRX_REQ_VALUE"\"";
static const char edrx_ptw[] = "AT%XPTW=4,\"0111\"";
.
.
static int w_lte_lc_init_and_connect(struct device *unused)
{
/* ADD HERE */
	if (at_cmd_write(offline, NULL, 0, NULL) != 0) {
		return -EIO;
	}

	if (at_cmd_write("AT+CNMI=3,2,0,1", NULL, 0, NULL) != 0) {
		return -EIO;
	}
/* ADD HERE */

#if defined(CONFIG_LTE_EDRX_REQ)
	/* Request configured eDRX settings to save power */
	if (at_cmd_write(edrx_req, NULL, 0, NULL) != 0) {
		return -EIO;
	}
	if (at_cmd_write(edrx_ptw, NULL, 0, NULL) != 0) {
		return -EIO;
	}
#endif
	if (at_cmd_write(subscribe, NULL, 0, NULL) != 0) {
		return -EIO;
	}

#if defined(CONFIG_LTE_LOCK_BANDS)
	/* Set LTE band lock (volatile setting).
	 * Has to be done every time before activating the modem.
	 */
	if (at_cmd_write(lock_bands, NULL, 0, NULL) != 0) {
		return -EIO;
	}
#endif
#if defined(CONFIG_LTE_LEGACY_PCO_MODE)
	if (at_cmd_write(legacy_pco, NULL, 0, NULL) != 0) {
		return -EIO;
	}
	LOG_INF("Using legacy LTE PCO mode...");
#endif
#if defined(CONFIG_LTE_PDP_CMD)
	if (at_cmd_write(cgdcont, NULL, 0, NULL) != 0) {
		return -EIO;
	}
	LOG_INF("PDP Context: %s", cgdcont);
#endif
	if (at_cmd_write(network_mode, NULL, 0, NULL) != 0) {
		return -EIO;
	}

	k_sem_init(&link, 0, 1);

	at_cmd_set_notification_handler(at_handler);

	if (at_cmd_write(normal, NULL, 0, NULL) != 0) {
		return -EIO;
	}

	k_sem_take(&link, K_FOREVER);

	at_cmd_set_notification_handler(NULL);

	return 0;
}

*Without SMS notification, AT+CNMI was reset and probably SMS is received.

/ncs/nrf/drivers/lte_link_control/lte_lc.c

In this lte_lc.c, I think at_cmd_set_notification_handler is related to this issue. Can you check this?

Another question:

Every time SMS is received, SMS notification is reset and you need to run "AT+CNMI=3,2,0,1" again. Why does this happen? Is this possible to set SMS notification permanently?

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Sat, 07 Sep 2019 04:51:11 GMT

oops! That's wrong.

This is correct.

AT+CEDRXS=2,4,"0110"

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Thu, 05 Sep 2019 15:54:30 GMT

AT+CEDRXRDP=4,"0110","0110","0000"
+CEDRXRDP: 0
OK

When I run the above AT command with at_client program, I received "+CEDRXRDP: 0."

But, studying the current consumption(floor: 40uA) and receiving interval, eDRX seems to be working in mqtt_simple + edrx, not at_client.

I guess something is missing.

What should I add? Any help?

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 04 Sep 2019 16:23:58 GMT

Hi, Hakon. Thank you for your advice. Very helpful.

>Is it NB1 or LTE M1?
LTE-M1, hologram SIM

>SMS reception should work in eDRX and PSM
I see. So it's worth to try to find a way of using SMS and eDRX at the same time in nRF9160.

If SMS and eDRX integrated sample program is provided, it's very helpful. I think the best way to send messages in some interval while checking an incoming message is to use eDRX and SMS.

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Wed, 04 Sep 2019 10:45:19 GMT

SMS reception should work in eDRX and PSM, but the SMS itself will be delayed by one period, so if the eDRX or PSM timeout is set to 1 hour, you might have to wait 1 hour to read the received SMS.

Which operator network are you connected to?

Is it NB1 or LTE M1?

[quote user="yusuke217"]Could u tell me how to set up eDRX on LTE link monitor?[/quote]

To request eDRX: eDRX setting +CEDRXS

To check if the settings were applied: Read EDRX dynamic parameters +CEDRXRDP

Kind regards,

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 04 Sep 2019 00:30:11 GMT

Could u tell me how to set up eDRX on LTE link monitor? I want to know the at commands for it.

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Mon, 02 Sep 2019 09:32:13 GMT

Yea, I can receive SMS in normal mode without PSM or eDRX.
I use at_client program and hologram SIM. The SIM allows you to send SMS.

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Mon, 02 Sep 2019 06:51:12 GMT

Hi,

Are you able to receive SMS successfully in other operating modes?

Is it just eDRX that is the problem?

Kind regards,

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Sun, 01 Sep 2019 03:14:40 GMT

Hi, Hakon.

I can't receive SMS in eDRX.

When I set 82 sec interval, I hope nRF9160 check if it receives SMS in that interval, but it doesn't work.

Does this mean SMS can't be received when you use eDRX?

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 17 Jul 2019 03:07:09 GMT

I think it's not possible to "wake up" dormant LTE modem by SMS. What you can do is to check SMS incoming in the interval which eDRX configures.

RE: How to receive SMS message in standby mode in nRF9160?

Ethan — Wed, 17 Jul 2019 01:28:55 GMT

The reference is not what we are doing. In the case, it is not sending trigger on SMS to wake up the LTE module. The article explains that once the LTE module becomes awake, it can receive SMS even though SMS is sent while the LTE module is off. What we want to do is to wake up the LTE module in eDRX or PSM by a trigger on SMS. Isn't it?

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Wed, 17 Jul 2019 01:03:42 GMT

SMS should be received even when eDRX or PSM is activated. SMS is kept at least three days if it doesn't reach a cell phone. You can turn off your cell phone, send SMS from another cell phone, and turn on the former one. You will receive SMS.

https://www.techwalla.com/articles/can-i-receive-texts-while-my-phone-is-off

RE: How to receive SMS message in standby mode in nRF9160?

Ethan — Tue, 16 Jul 2019 23:36:03 GMT

Thanks for your response.

I see. You are also facing with the same difficulty as ours. Since eDRX and PSM extend the paging period, the LTE becomes dormant and cannot receive any signals during the period. Only thing we can think of now is to trigger the LTE from microchip in the device, which we don't want.

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Tue, 16 Jul 2019 22:44:42 GMT

In my case, I'm trying to receive SMS during eDRX. If it received SMS, it's supposed to send data through UDP.

However, I have not been able to do that.

I really want an example program about this.

RE: How to receive SMS message in standby mode in nRF9160?

Ethan — Tue, 16 Jul 2019 20:59:16 GMT

Hi Yusuke, sounds like your development would be similar to ours. I am wondering that when you succeeded in implementing MQTT(+TLS) to wake up the device and send some data by UDP, is the LTE module in PSM? Did you successfully implement SMS function? I have been trying to implement the method to wake up the LTE by sending SMS and send some data to the server by UDP. If you don't mind, please exchange the information. Thanks

RE: How to receive SMS message in standby mode in nRF9160?

Håkon Alseth — Mon, 08 Jul 2019 08:08:26 GMT

The sample you link to is for sending sms. For receiving sms, you need to poll the AT socket. Try to use at_client, and see if you are able to get a sms successfully received. Note that you need a SIM card which has a phone number in order to send/receive sms.

Kind regards,

Håkon

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Sat, 06 Jul 2019 05:40:36 GMT

This is draft code of what I want to do.

/*
 * Copyright (c) 2018 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: LicenseRef-BSD-5-Clause-Nordic
 */

#include <zephyr.h>
#include <net/socket.h>
#include <stdio.h>
#include <uart.h>
#include <string.h>

/**@brief Recoverable BSD library error. */
void bsd_recoverable_error_handler(uint32_t err)
{
	printk("bsdlib recoverable error: %u\n", err);
}

/**@brief Irrecoverable BSD library error. */
void bsd_irrecoverable_error_handler(uint32_t err)
{
	printk("bsdlib irrecoverable error: %u\n", err);

	__ASSERT_NO_MSG(false);
}

int blocking_recv(int fd, u8_t *buf, u32_t size, u32_t flags)
{
	int err;

	do {
		err = recv(fd, buf, size, flags);
	} while (err < 0 && errno == EAGAIN);

	return err;
}

int blocking_send(int fd, u8_t *buf, u32_t size, u32_t flags)
{
	int err;

	do {
		err = send(fd, buf, size, flags);
	} while (err < 0 && errno == EAGAIN);

	return err;
}

int blocking_connect(int fd, struct sockaddr *local_addr, socklen_t len)
{
	int err;

	do {
		err = connect(fd, local_addr, len);
	} while (err < 0 && errno == EAGAIN);

	return err;
}

void setup_sms()
{
    char recv_buf[256 + 1];
    const char *at_commands[] = {<AT Commands that enables modem and SMS notification>};
	int at_socket_fd = socket(AF_LTE, 0, NPROTO_AT);

	printk("Starting simple AT socket application\n\r");

	if (at_socket_fd < 0) {
		printk("Socket err: %d, errno: %d\r\n", at_socket_fd, errno);
	}
	for (int i = 0; i < ARRAY_SIZE(at_commands); i++) {
        printk("%s\n", at_commands[i]);
		int bytes_written = send(at_socket_fd, at_commands[i], strlen(at_commands[i]), 0);
		if (bytes_written > 0) {
			int r_bytes = blocking_recv(at_socket_fd, recv_buf, sizeof(recv_buf), MSG_DONTWAIT);
			if (r_bytes > 0) {
				printk("%s\n", recv_buf);
			}
		}
	}
	printk("Closing socket\n\r");
	(void)close(at_socket_fd);
}

void main(void)
{
	printk("The SMS receiving sample started\n");
	char sms_messsage[30];
    setup_sms();

    while(1){
        while(<no SMS message? = true>){
            <check if modem is on and SMS notification is on in some interval>;
            if(<modem is off of SMS notification is off>){
                setup_sms();
            }
        }
        
        // if SMS received
        <store sms message to sms_messsage>;
        printk("SMS message is %s\n", sms_message);
    };

}

RE: How to receive SMS message in standby mode in nRF9160?

Yusuke — Thu, 04 Jul 2019 15:30:15 GMT

I've already checked the link below, but I don't really get what each line means.
devzone.nordicsemi.com/.../sending-sms-using-at_client-example

This is my understanding.

----------------
AT+CFUN=1
=> Turn on the modem. The modem can receive SMS at any time.

AT+CPIN="1234"
=> Set Pin number, which is a password of SIM.

AT+CNMI=3,2,0,1
=> Configure the process of receving SMS.
----------------

After this setting, MCU can go to sleep to wait until SMS is received. When SMS is received, MCU wakes up.

Is this correct? I'm not familiar with SMS function. Sorry for poor skill.