Why board is booting with SD card without press S2 button?

Mine is BBB wireless, flashed system
bone-debian-10.10-iot-armhf-2021-08-09-4gb.img into eMMC and works without insert SD card.

I prepared a SD card that flashed bone-debian-10.10-lxqt-armhf-2021-08-09-4gb.img, then insert into BBB wireless and power cable plugged, then system boot with SD card directly.

Is it normal ? then how to boot with eMMC when inserted a SD card?

Here is the console log:

[ 243.283625] watchdog: watchdog0: watchdog did not stop!
[ 243.609968] reboot: Restarting system

U-Boot SPL 2019.04-g047fc48 (Aug 05 2021 - 00:39:11 +0000)
Trying to boot from MMC2
Loading Environment from EXT4… ** File not found /boot/uboot.env **

** Unable to read “/boot/uboot.env” from mmc0:1 **

U-Boot 2019.04-g047fc48 (Aug 05 2021 - 00:39:11 +0000)

CPU : AM335X-GP rev 2.1
I2C: ready
DRAM: 512 MiB
No match for driver ‘omap_hsmmc’
No match for driver ‘omap_hsmmc’
Some drivers were not found
Reset Source: Global warm SW reset has occurred.
Reset Source: Power-on reset has occurred.
RTC 32KCLK Source: External.
MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1
Loading Environment from EXT4… ** File not found /boot/uboot.env **

** Unable to read “/boot/uboot.env” from mmc0:1 **
Board: BeagleBone Black
not set. Validating first E-fuse MAC
BeagleBone Black:
Model: BeagleBoard.org BeagleBone Black Wireless:
BeagleBone Cape EEPROM: no EEPROM at address: 0x54
BeagleBone Cape EEPROM: no EEPROM at address: 0x55
BeagleBone Cape EEPROM: no EEPROM at address: 0x56
BeagleBone Cape EEPROM: no EEPROM at address: 0x57
Net: eth0: MII MODE
Could not get PHY for cpsw: addr 0
cpsw, usb_ether
Press SPACE to abort autoboot in 0 seconds
board_name=[BBBW] …
switch to partitions #0, OK
mmc0 is current device
SD/MMC found on device 0
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1…
gpio: pin 56 (gpio 56) value is 0
gpio: pin 55 (gpio 55) value is 0
gpio: pin 54 (gpio 54) value is 0
gpio: pin 53 (gpio 53) value is 1
switch to partitions #0, OK
mmc0 is current device
gpio: pin 54 (gpio 54) value is 1
Checking for: /uEnv.txt …
Checking for: /boot.scr …
Checking for: /boot/boot.scr …
Checking for: /boot/uEnv.txt …
gpio: pin 55 (gpio 55) value is 1
2057 bytes read in 32 ms (62.5 KiB/s)
Loaded environment from /boot/uEnv.txt
Checking if uname_r is set in /boot/uEnv.txt…
gpio: pin 56 (gpio 56) value is 1
Running uname_boot …
loading /boot/vmlinuz-4.19.94-ti-r64 …
10166784 bytes read in 906 ms (10.7 MiB/s)
debug: [enable_uboot_overlays=1] …
debug: [enable_uboot_cape_universal=1] …
debug: [uboot_base_dtb_univ=am335x-boneblack-uboot-univ.dtb] …
uboot_overlays: [uboot_base_dtb=am335x-boneblack-uboot-univ.dtb] …
uboot_overlays: Switching too: dtb=am335x-boneblack-uboot-univ.dtb …
loading /boot/dtbs/4.19.94-ti-r64/am335x-boneblack-uboot-univ.dtb …
164234 bytes read in 152 ms (1 MiB/s)
uboot_overlays: [fdt_buffer=0x60000] …
uboot_overlays: loading /lib/firmware/BB-ADC-00A0.dtbo …
650 bytes read in 160 ms (3.9 KiB/s)
uboot_overlays: loading /lib/firmware/BB-BONE-eMMC1-01-00A0.dtbo …
1584 bytes read in 425 ms (2.9 KiB/s)
uboot_overlays: loading /lib/firmware/BB-HDMI-TDA998x-00A0.dtbo …
4915 bytes read in 601 ms (7.8 KiB/s)
uboot_overlays: loading /lib/firmware/BB-BBBW-WL1835-00A0.dtbo …
4156 bytes read in 93 ms (43 KiB/s)
uboot_overlays: loading /lib/firmware/AM335X-PRU-RPROC-4-19-TI-00A0.dtbo …
3653 bytes read in 360 ms (9.8 KiB/s)
loading /boot/initrd.img-4.19.94-ti-r64 …
11817550 bytes read in 1052 ms (10.7 MiB/s)
debug: [console=ttyS0,115200n8 bone_capemgr.uboot_capemgr_enabled=1 root=/dev/mmcblk0p1 ro rootfstype=ext4 rootwait coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_qua.
debug: [bootz 0x82000000 0x88080000:b4524e 88000000] …

Flattened Device Tree blob at 88000000

Booting using the fdt blob at 0x88000000
Loading Ramdisk to 8f4ba000, end 8ffff24e … OK
Loading Device Tree to 8f42d000, end 8f4b9fff … OK

Starting kernel …

[ 0.002245] timer_probe: no matching timers found
[ 0.194438] l4_wkup_cm:clk:0010:0: failed to disable
[ 1.764252] omap_voltage_late_init: Voltage driver support not added
[ 21.584218] systemd[1]: System cannot boot: Missing /etc/machine-id and /etc is mounted read-only.
[ 21.593428] systemd[1]: Booting up is supported only when:
[ 21.599038] systemd[1]: 1) /etc/machine-id exists and is populated.
[ 21.605419] systemd[1]: 2) /etc/machine-id exists and is empty.
[ 21.611411] systemd[1]: 3) /etc/machine-id is missing and /etc is writable.
Starting Create Volatile Files and Directories…
[ OK ] Started Create Volatile Files and Directories.
Starting Network Time Synchronization…
Starting Update UTMP about System Boot/Shutdown…
[ OK ] Started Entropy daemon using the HAVEGE algorithm.
[ OK ] Started udev Kernel Device Manager.
[ OK ] Started Update UTMP about System Boot/Shutdown.
[ OK ] Started udev Coldplug all Devices.
Starting Show Plymouth Boot Screen…
Starting Helper to synchronize boot up for ifupdown…
[ OK ] Started Helper to synchronize boot up for ifupdown.
Starting Raise network interfaces…
[ OK ] Started Show Plymouth Boot Screen.
[ OK ] Started Forward Password R…s to Plymouth Directory Watch.
[ OK ] Reached target Paths.
[ OK ] Reached target Local Encrypted Volumes.
[ OK ] Started Network Time Synchronization.
[ OK ] Reached target System Time Synchronized.
[ OK ] Reached target System Initialization.
[ OK ] Listening on Cloud9 Socket.
[ OK ] Started Daily Cleanup of Temporary Directories.
[ OK ] Listening on Node-RED Socket.
[ OK ] Listening on bonescript.socket.
[ OK ] Listening on D-Bus System Message Bus Socket.
[ OK ] Listening on Avahi mDNS/DNS-SD Stack Activation Socket.
[ OK ] Reached target Sockets.
[ OK ] Reached target Basic System.
Starting BBAI brcmfmac tether Service…
Starting System Logging Service…
Starting robotcontrol…
[ OK ] Started D-Bus System Message Bus.
Starting Connection service…
Starting LSB: Load kernel …d to enable cpufreq scaling…
Starting Avahi mDNS/DNS-SD Stack…
Starting Disk Manager…
Starting rc_battery_monitor…
[ OK ] Started Bonescript autorun.
Starting BB WL18xx wlan0 Service…
Starting WPA supplicant…
[ OK ] Started Regular background program processing daemon.
Starting Login Service…
[ OK ] Started Daily rotation of log files.
[ OK ] Reached target Timers.
[ OK ] Started System Logging Service.
[ OK ] Started Raise network interfaces.
[ OK ] Started robotcontrol.
[ OK ] Started rc_battery_monitor.
[ OK ] Started BBAI brcmfmac tether Service.
[ OK ] Started Login Service.
[ OK ] Started WPA supplicant.
[ OK ] Started Connection service.
[ OK ] Started Avahi mDNS/DNS-SD Stack.
[ OK ] Reached target Network.
Starting OpenBSD Secure Shell server…
Starting Permit User Sessions…
Starting A high performanc… and a reverse proxy server…
Starting Generic Board Startup…
Starting Authorization Manager…
[ OK ] Started Permit User Sessions.
Starting Hostname Service…
Starting Hold until boot process finishes up…
Starting Light Display Manager…
[ OK ] Started LSB: Load kernel m…ded to enable cpufreq scaling.
[ OK ] Stopped OpenBSD Secure Shell server.
[ OK ] Started Authorization Manager.
Starting LSB: set CPUFreq kernel parameters…
[ OK ] Started LSB: set CPUFreq kernel parameters.
[ OK ] Started Hostname Service.
[ OK ] Started A high performance…er and a reverse proxy server.

Debian GNU/Linux 10 beaglebone ttyS0

BeagleBoard.org Debian Buster LXQt Image 2021-08-09

Support: https://bbb.io/debian

default username:password is [debian:temppwd]

beaglebone login: [ 119.749695] wkup_m3_ipc 44e11324.wkup_m3_ipc: could not get rproc handle
[ 120.539726] PM: Cannot get wkup_m3_ipc handle
???[ 125.185171] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j) sak(k) show-backt
[ 125.218499] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j)?.??backt?
Debian GNU/Linux 10 beaglebone ttyS0

BeagleBoard.org Debian Buster LXQt Image 2021-08-09

Support: https://bbb.io/debian

default username:password is [debian:temppwd]

beaglebone login:

Any suggestion will be appreciated.

U-Boot searches for /boot/uEnv.txt, and if found boots from that media…

so don’t have that file…

Regards,