Understanding the API calls.

[SamIam]

nRf Gurus, I need your help!
It is very hard for me to understand top level configuration of the soft devices and overall mentality. I am sure it will be very easy and convenient as soon as I will understand how to interact with these soft-devices and modems. Can anyone PLEASE(!) present a bare code in a single "main" function and "includes'', if any needed.
The goal is to start the device, send "AT+CFUN?" and read the result back into variable with API or using AT-library.
This will be a great help to understand how everything else is structured over here.

[Hakon]

Hi,

 

The goal is to start the device, send "AT+CFUN?" and read the result back into variable with API or using AT-library.

 You can use the at_cmd_write() function for that. The result will be read back into a buffer that you pass to the function.

 

Can anyone PLEASE(!) present a bare code in a single "main" function and "includes'', if any needed.

 You can use most samples in the SDK. This one is quite simple.

[SamIam]

Thank you for your support.
I got over the AT_Library and modified the sample to check both, "at_cmd_write" and "at_cmd_write_with_callback" functions. For the debugging convenience i used "spagetti" style instead of looping and still need a small help with callbacks. While "at_cmd_write" is working great, it looks like handler routine for "at_cmd_write_with_callback" ("responce_handler" in this case) does not have IRQ priority and not getting called while code is running.
As you can see on the terminal, "at_cmd_write" replied right back, but handler of "at_cmd_write_with_callback" waited until "main" got through and only then kicked in. It is really important for me to properly arrange the sequence of the logging in to the server, what am I doing wrong?
How can I get the handler to be a priority interrupt?

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

#include <zephyr.h>
#include <stdio.h>
#include <drivers/uart.h>
#include <string.h>
#include <drivers/clock_control.h>
#include <drivers/clock_control/nrf_clock_control.h>

//enum at_cmd_state at_state;

/**@brief Recoverable modem library error. */




void nrf_modem_recoverable_error_handler(uint32_t err)
{
	printk("Modem library recoverable error: %u\n", err);
}

/* To strictly comply with UART timing, enable external XTAL oscillator */
void enable_xtal(void)
{
	struct onoff_manager *clk_mgr;
	static struct onoff_client cli = {};

	clk_mgr = z_nrf_clock_control_get_onoff(CLOCK_CONTROL_NRF_SUBSYS_HF);
	sys_notify_init_spinwait(&cli.notify);
	(void)onoff_request(clk_mgr, &cli);
}

static void responce_handler(const char* response){
    if(strlen(response) > 0){
        printk("AT recv:\t%s",response);}
}

void main(void)
{
        int err;
        char rback[20];
	enable_xtal();
        nrfx_systick_init();//Sam
	printk("The AT host sample started\n");
        nrfx_systick_delay_ms(1000);  
           
        printk("Sending AT+CFUN=1\n");
        if((err = at_cmd_write_with_callback("AT+CFUN=1",&responce_handler)) !=0)
        { printk("Return: Error\n", err);}
        else 
          {printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(10);
        printk("Sending AT+CFUN?\n");
        //if((err = at_cmd_write_with_callback("AT+CFUN?",&responce_handler)) !=0)
        if((err = at_cmd_write("AT+CFUN?",&rback,sizeof(rback),NULL) !=0))
          {printk("Return: Error\n", err);}
        else 
          {printk(rback,"\n");
            printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(1000); 
        /*******************************************/
        printk("Requesting MFG ID\n");
        if((err = at_cmd_write_with_callback("AT+CGMI?",&responce_handler)) !=0)
        { printk("Return: Error\n", err);}
        else 
          {printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(10);
        /*******************************************/
        printk("Requesting Temp\n");
        if((err = at_cmd_write_with_callback("AT%XTEMP?",&responce_handler)) !=0)
        { printk("Return: Error\n", err);}
        else 
          {printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(1000);
        /*******************************************/
        printk("Sending AT+CFUN=0\n");
        if((err = at_cmd_write_with_callback("AT+CFUN=0",&responce_handler)) !=0)
        { printk("Return: Error\n", err);}
        else 
          {printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(10);
                printk("Sending AT+CFUN?\n");
        if((err = at_cmd_write_with_callback("AT+CFUN?",&responce_handler)) !=0)
        { printk("Return: Error\n", err);}
        else 
          {printk("Return: OK\n", err);}
        nrfx_systick_delay_ms(10);
              
}

The AT host sample started
Sending AT+CFUN=1
Return: OK
Sending AT+CFUN?
+CFUN: 1
Return: OK
Requesting MFG ID
Return: OK
Requesting Temp
Return: OK
Sending AT+CFUN=0
Return: OK
Sending AT+CFUN?
Return: OK
AT recv:%XTEMP: 27
AT recv:+CFUN: 0

[Hakon]

You can try changing the priority of the at cmd thread. You can do that by setting CONFIG_AT_CMD_THREAD_PRIO in prj.conf.