Problem with not entering serial recovery mode with nRF5340

RE: Problem with not entering serial recovery mode with nRF5340

Einar Thorsrud — Fri, 20 Oct 2023 09:02:36 GMT

I see, that is strange. Do you use the exact same firmware on the DK as on the custom board with the NORA-B101-00B module? Meaning the exact same hex files? For such a simple sample, and with this test firmware where you have disabled the LFXO, that should work on both the board with NORA-B101-00B and the DK. If it does not, we need to look more closely at the HW and how you test to see where there could be any differences.

RE: Problem with not entering serial recovery mode with nRF5340

kudo — Thu, 19 Oct 2023 00:41:48 GMT

Hi Einar,

[quote userid="7377" url="~/f/nordic-q-a/104797/problem-with-not-entering-serial-recovery-mode-with-nrf5340/451098"]When I test this on the nRF5340 DK, recovery mode is entered when 1.15 is high, which is the same as you see from what I understand?[/quote]

Yes, the behavior is the same.
Inputting High to P1.15 will enter recovery mode.

[quote userid="7377" url="~/f/nordic-q-a/104797/problem-with-not-entering-serial-recovery-mode-with-nrf5340/451098"]When it comes to your custom board I am not able to test that, but I wonder if you have double checked that P1.15 is actually connected?[/quote]

Yes, we have confirmed that the custom board's FW is able to detect P1.15 using the code below based on the hello_world sample.

nrf5340dk_nrf5340_cpuapp_ns.overlay :

/ {
	buttons {
		compatible = "gpio-keys";
		bootkey: boot_key {
			gpios = <&gpio1 15 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
			label = "boot start key";
		};
    };
	aliases {
        tp0 = &bootkey;
    };
};

&spi4{
    status = "disabled";
};

main.c:

#include <zephyr/kernel.h>
#include <zephyr/device.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/sys/printk.h>

#define SLEEP_TIME_MS	1000

#define TP0_NODE	DT_ALIAS(tp0)
#if !DT_NODE_HAS_STATUS(TP0_NODE, okay)
#error "Unsupported board: tp0 devicetree alias is not defined"
#endif
static const struct gpio_dt_spec testpin = GPIO_DT_SPEC_GET_OR(TP0_NODE, gpios,
								  {0});

void main(void)
{
	int ret;
	
	printk("Hello World! %s\n", CONFIG_BOARD);

	if (!device_is_ready(testpin.port)) {
		printk("Error: testpin device %s is not ready\n",
		       testpin.port->name);
		return;
	}

	ret = gpio_pin_configure_dt(&testpin, GPIO_INPUT);
	if (ret != 0) {
		printk("Error %d: failed to configure %s pin %d\n",
		       ret, testpin.port->name, testpin.pin);
		return;
	}

	while (1) {
		int val = gpio_pin_get_dt(&testpin);
		
		if (val > 0) {
			printk("pin high\n");
		}
		else if (val == 0) {
			printk("pin low\n");
		}
		
		k_msleep(SLEEP_TIME_MS);
	}
}

RE: Problem with not entering serial recovery mode with nRF5340

Einar Thorsrud — Wed, 18 Oct 2023 14:18:05 GMT

Hi,

When I test this on the nRF5340 DK, recovery mode is entered when 1.15 is high, which is the same as you see from what I understand? When it comes to your custom board I am not able to test that, but I wonder if you have double checked that P1.15 is actually connected? Are you able to read both a high a and a low state on that pin on your custom board with a simple test firmware just to rule out that as an issue?