debian@beaglebone:~$ dmesg
[ 0.000000] Booting Linux on physical CPU 0x0
[ 0.000000] Linux version 4.9.78-ti-r94 (root@b2-am57xx-beagle-x15-2gb) (gcc version 6.3.0 20170516 (Debian 6.3.0-18) ) #1 SMP PREEMPT Fri Jan 26 21:26:24 UTC 2018
[ 0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[ 0.000000] OF: fdt:Machine model: TI AM335x BeagleBone Black
[ 0.000000] cma: Reserved 48 MiB at 0x9c800000
[ 0.000000] Memory policy: Data cache writeback
[ 0.000000] On node 0 totalpages: 130560
[ 0.000000] free_area_init_node: node 0, pgdat c14e97c0, node_mem_map df961000
[ 0.000000] Normal zone: 1148 pages used for memmap
[ 0.000000] Normal zone: 0 pages reserved
[ 0.000000] Normal zone: 130560 pages, LIFO batch:31
[ 0.000000] CPU: All CPU(s) started in SVC mode.
[ 0.000000] AM335X ES2.1 (sgx neon)
[ 0.000000] percpu: Embedded 15 pages/cpu @df927000 s31884 r8192 d21364 u61440
[ 0.000000] pcpu-alloc: s31884 r8192 d21364 u61440 alloc=15*4096
[ 0.000000] pcpu-alloc: [0] 0
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 129412
[ 0.000000] Kernel command line: console=ttyO0,115200n8 bone_capemgr.enable_partno=BB-UART1,BB-UART4 bone_capemgr.uboot_capemgr_enabled=1 root=/dev/mmcblk1p1 ro rootfstype=ext4 rootwait coherent_pool=1M net.ifnames=0 quiet
[ 0.000000] PID hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.000000] Dentry cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.000000] Inode-cache hash table entries: 32768 (order: 5, 131072 bytes)
[ 0.000000] Memory: 439684K/522240K available (12288K kernel code, 1153K rwdata, 4356K rodata, 1024K init, 751K bss, 33404K reserved, 49152K cma-reserved, 0K highmem)
[ 0.000000] Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xffc00000 - 0xfff00000 (3072 kB)
vmalloc : 0xe0000000 - 0xff800000 ( 504 MB)
lowmem : 0xc0000000 - 0xdfe00000 ( 510 MB)
pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
.text : 0xc0008000 - 0xc0d00000 (13280 kB)
.init : 0xc1300000 - 0xc1400000 (1024 kB)
.data : 0xc1400000 - 0xc1520770 (1154 kB)
.bss : 0xc1522000 - 0xc15ddfb0 ( 752 kB)
[ 0.000000] Preemptible hierarchical RCU implementation.
[ 0.000000] Build-time adjustment of leaf fanout to 32.
[ 0.000000] RCU restricting CPUs from NR_CPUS=2 to nr_cpu_ids=1.
[ 0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=32, nr_cpu_ids=1
[ 0.000000] NR_IRQS:16 nr_irqs:16 16
[ 0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts
[ 0.000000] OMAP clockevent source: timer2 at 24000000 Hz
[ 0.000019] sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 89478484971ns
[ 0.000037] clocksource: timer1: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 79635851949 ns
[ 0.000048] OMAP clocksource: timer1 at 24000000 Hz
[ 0.000945] clocksource_probe: no matching clocksources found
[ 0.001412] Console: colour dummy device 80x30
[ 0.001440] WARNING: Your 'console=ttyO0' has been replaced by 'ttyS0'
[ 0.001445] This ensures that you still see kernel messages. Please
[ 0.001450] update your kernel commandline.
[ 0.001472] Calibrating delay loop... 995.32 BogoMIPS (lpj=1990656)
[ 0.046589] pid_max: default: 32768 minimum: 301
[ 0.046884] Security Framework initialized
[ 0.046895] Yama: becoming mindful.
[ 0.046955] AppArmor: AppArmor initialized
[ 0.047168] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes)
[ 0.047179] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)
[ 0.048385] CPU: Testing write buffer coherency: ok
[ 0.048454] ftrace: allocating 39651 entries in 117 pages
[ 0.161208] CPU0: thread -1, cpu 0, socket -1, mpidr 0
[ 0.161273] Setting up static identity map for 0x80100000 - 0x80100060
[ 0.206610] Brought up 1 CPUs
[ 0.206630] SMP: Total of 1 processors activated (995.32 BogoMIPS).
[ 0.206637] CPU: All CPU(s) started in SVC mode.
[ 0.208254] devtmpfs: initialized
[ 0.231007] VFP support v0.3: implementor 41 architecture 3 part 30 variant c rev 3
[ 0.231569] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[ 0.231595] futex hash table entries: 256 (order: 2, 16384 bytes)
[ 0.235394] xor: measuring software checksum speed
[ 0.274625] arm4regs : 1217.000 MB/sec
[ 0.314576] 8regs : 1091.000 MB/sec
[ 0.354575] 32regs : 1088.000 MB/sec
[ 0.394574] neon : 1658.000 MB/sec
[ 0.394581] xor: using function: neon (1658.000 MB/sec)
[ 0.394598] pinctrl core: initialized pinctrl subsystem
[ 0.396169] NET: Registered protocol family 16
[ 0.400006] DMA: preallocated 1024 KiB pool for atomic coherent allocations
[ 0.428347] omap_hwmod: debugss: _wait_target_disable failed
[ 0.478621] cpuidle: using governor ladder
[ 0.490602] cpuidle: using governor menu
[ 0.499755] OMAP GPIO hardware version 0.1
[ 0.521700] No ATAGs?
[ 0.521723] hw-breakpoint: debug architecture 0x4 unsupported.
[ 0.522016] omap4_sram_init:Unable to allocate sram needed to handle errata I688
[ 0.522027] omap4_sram_init:Unable to get sram pool needed to handle errata I688
[ 0.634627] raid6: neonx2 gen() 1894 MB/s
[ 0.702614] raid6: neonx2 xor() 1169 MB/s
[ 0.702621] raid6: using algorithm neonx2 gen() 1894 MB/s
[ 0.702627] raid6: .... xor() 1169 MB/s, rmw enabled
[ 0.702634] raid6: using intx1 recovery algorithm
[ 0.712766] edma 49000000.edma: TI EDMA DMA engine driver
[ 0.716668] SCSI subsystem initialized
[ 0.718749] libata version 3.00 loaded.
[ 0.719126] usbcore: registered new interface driver usbfs
[ 0.719200] usbcore: registered new interface driver hub
[ 0.719319] usbcore: registered new device driver usb
[ 0.719985] omap_i2c 44e0b000.i2c: could not find pctldev for node /ocp/l4_wkup@44c00000/scm@210000/pinmux@800/pinmux_i2c0_pins, deferring probe
[ 0.721574] omap_i2c 4819c000.i2c: bus 2 rev0.11 at 100 kHz
[ 0.721828] media: Linux media interface: v0.10
[ 0.721894] Linux video capture interface: v2.00
[ 0.721995] pps_core: LinuxPPS API ver. 1 registered
[ 0.722001] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <
giom...@linux.it>
[ 0.722027] PTP clock support registered
[ 0.723060] omap-mailbox 480c8000.mailbox: omap mailbox rev 0x400
[ 0.726991] Advanced Linux Sound Architecture Driver Initialized.
[ 0.727822] NetLabel: Initializing
[ 0.727833] NetLabel: domain hash size = 128
[ 0.727838] NetLabel: protocols = UNLABELED CIPSOv4
[ 0.727912] NetLabel: unlabeled traffic allowed by default
[ 0.731075] clocksource: Switched to clocksource timer1
[ 0.859418] VFS: Disk quotas dquot_6.6.0
[ 0.859534] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[ 0.859952] AppArmor: AppArmor Filesystem Enabled
[ 0.875274] NET: Registered protocol family 2
[ 0.876301] TCP established hash table entries: 4096 (order: 2, 16384 bytes)
[ 0.876347] TCP bind hash table entries: 4096 (order: 3, 32768 bytes)
[ 0.876405] TCP: Hash tables configured (established 4096 bind 4096)
[ 0.876476] UDP hash table entries: 256 (order: 1, 8192 bytes)
[ 0.876496] UDP-Lite hash table entries: 256 (order: 1, 8192 bytes)
[ 0.876701] NET: Registered protocol family 1
[ 0.885675] RPC: Registered named UNIX socket transport module.
[ 0.885684] RPC: Registered udp transport module.
[ 0.885689] RPC: Registered tcp transport module.
[ 0.885694] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 0.885711] PCI: CLS 0 bytes, default 64
[ 0.886417] Unpacking initramfs...
[ 1.091144] random: fast init done
[ 1.341571] Freeing initrd memory: 6156K
[ 1.342202] hw perfevents: enabled with armv7_cortex_a8 PMU driver, 5 counters available
[ 1.345390] audit: initializing netlink subsys (disabled)
[ 1.345489] audit: type=2000 audit(1.272:1): initialized
[ 1.351109] workingset: timestamp_bits=14 max_order=17 bucket_order=3
[ 1.351295] zbud: loaded
[ 1.356555] NFS: Registering the id_resolver key type
[ 1.356594] Key type id_resolver registered
[ 1.356600] Key type id_legacy registered
[ 1.356624] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[ 1.357037] fuse init (API version 7.26)
[ 1.357466] orangefs_debugfs_init: called with debug mask: :none: :0:
[ 1.357742] orangefs_init: module version upstream loaded
[ 1.357751] SGI XFS with ACLs, security attributes, realtime, no debug enabled
[ 1.378266] Key type asymmetric registered
[ 1.378281] Asymmetric key parser 'x509' registered
[ 1.378415] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 245)
[ 1.382712] io scheduler noop registered
[ 1.382722] io scheduler deadline registered
[ 1.382815] io scheduler cfq registered (default)
[ 1.384802] pinctrl-single 44e10800.pinmux: 142 pins at pa f9e10800 size 568
[ 1.385868] gpio-of-helper ocp:cape-universal: ready
[ 1.389365] wkup_m3_ipc 44e11324.wkup_m3_ipc: could not get rproc handle
[ 1.390868] Serial: 8250/16550 driver, 6 ports, IRQ sharing disabled
[ 1.394646] 44e09000.serial: ttyS0 at MMIO 0x44e09000 (irq = 158, base_baud = 3000000) is a 8250
[ 1.407608] console [ttyS0] enabled
[ 1.408676] 48022000.serial: ttyS1 at MMIO 0x48022000 (irq = 159, base_baud = 3000000) is a 8250
[ 1.409587] 481a8000.serial: ttyS4 at MMIO 0x481a8000 (irq = 160, base_baud = 3000000) is a 8250
[ 1.412108] omap_rng 48310000.rng: OMAP Random Number Generator ver. 20
[ 1.412406] [drm] Initialized
[ 1.414713] at24 2-0054: 32768 byte 24c256 EEPROM, writable, 1 bytes/write
[ 1.415230] at24 2-0055: 32768 byte 24c256 EEPROM, writable, 1 bytes/write
[ 1.415517] at24 2-0056: 32768 byte 24c256 EEPROM, writable, 1 bytes/write
[ 1.415755] at24 2-0057: 32768 byte 24c256 EEPROM, writable, 1 bytes/write
[ 1.420326] libphy: Fixed MDIO Bus: probed
[ 1.421346] CAN device driver interface
[ 1.475118] davinci_mdio 4a101000.mdio: davinci mdio revision 1.6
[ 1.475135] davinci_mdio 4a101000.mdio: detected phy mask fffffffe
[ 1.475550] davinci_mdio: dt: updated phy_id[0] from phy_mask[fffffffe]
[ 1.489874] libphy: 4a101000.mdio: probed
[ 1.489903] davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver SMSC LAN8710/LAN8720
[ 1.490844] cpsw 4a100000.ethernet: Detected MACID = b0:d5:cc:fc:6d:f1
[ 1.490986] cpsw 4a100000.ethernet: cpts: overflow check period 1250 (jiffies)
[ 1.494370] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 1.494432] ehci-pci: EHCI PCI platform driver
[ 1.494511] ehci-platform: EHCI generic platform driver
[ 1.494734] ehci-omap: OMAP-EHCI Host Controller driver
[ 1.495695] usbcore: registered new interface driver usb-storage
[ 1.498154] 47401300.usb-phy supply vcc not found, using dummy regulator
[ 1.504198] 47401b00.usb-phy supply vcc not found, using dummy regulator
[ 1.508215] musb-hdrc musb-hdrc.1: MUSB HDRC host driver
[ 1.508261] musb-hdrc musb-hdrc.1: new USB bus registered, assigned bus number 1
[ 1.508581] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
[ 1.508591] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 1.508599] usb usb1: Product: MUSB HDRC host driver
[ 1.508606] usb usb1: Manufacturer: Linux 4.9.78-ti-r94 musb-hcd
[ 1.508614] usb usb1: SerialNumber: musb-hdrc.1
[ 1.509668] hub 1-0:1.0: USB hub found
[ 1.509732] hub 1-0:1.0: 1 port detected
[ 1.523373] omap_rtc 44e3e000.rtc: rtc core: registered 44e3e000.rtc as rtc0
[ 1.524994] i2c /dev entries driver
[ 1.527385] omap_wdt: OMAP Watchdog Timer Rev 0x01: initial timeout 60 sec
[ 1.528814] cpuidle: enable-method property 'ti,am3352' found operations
[ 1.529854] omap_hsmmc 48060000.mmc: Got CD GPIO
[ 1.608734] ledtrig-cpu: registered to indicate activity on CPUs
[ 1.609144] omap-aes 53500000.aes: OMAP AES hw accel rev: 3.2
[ 1.609602] omap-aes 53500000.aes: will run requests pump with realtime priority
[ 1.615768] omap-sham 53100000.sham: hw accel on OMAP rev 4.3
[ 1.618186] hidraw: raw HID events driver (C) Jiri Kosina
[ 1.619307] usbcore: registered new interface driver usbhid
[ 1.619317] usbhid: USB HID core driver
[ 1.620917] remoteproc remoteproc0: wkup_m3 is available
[ 1.622728] ti_am3359-tscadc 44e0d000.tscadc: chan 0 step_avg truncating to 16
[ 1.622742] ti_am3359-tscadc 44e0d000.tscadc: chan 1 step_avg truncating to 16
[ 1.622750] ti_am3359-tscadc 44e0d000.tscadc: chan 2 step_avg truncating to 16
[ 1.622758] ti_am3359-tscadc 44e0d000.tscadc: chan 3 step_avg truncating to 16
[ 1.622765] ti_am3359-tscadc 44e0d000.tscadc: chan 4 step_avg truncating to 16
[ 1.622773] ti_am3359-tscadc 44e0d000.tscadc: chan 5 step_avg truncating to 16
[ 1.622780] ti_am3359-tscadc 44e0d000.tscadc: chan 6 step_avg truncating to 16
[ 1.630595] wireguard: WireGuard 0.0.20180118 loaded. See
www.wireguard.com for information.
[ 1.630608] wireguard: Copyright (C) 2015-2018 Jason A. Donenfeld <
Ja...@zx2c4.com>. All Rights Reserved.
[ 1.630998] NET: Registered protocol family 10
[ 1.636666] mip6: Mobile IPv6
[ 1.636691] NET: Registered protocol family 17
[ 1.636710] can: controller area network core (rev 20120528 abi 9)
[ 1.636782] NET: Registered protocol family 29
[ 1.636901] Key type dns_resolver registered
[ 1.636908] mpls_gso: MPLS GSO support
[ 1.637249] omap_voltage_late_init: Voltage driver support not added
[ 1.644584] PM: Cannot get wkup_m3_ipc handle
[ 1.649294] ThumbEE CPU extension supported.
[ 1.649322] Registering SWP/SWPB emulation handler
[ 1.650652] registered taskstats version 1
[ 1.650797] zswap: loaded using pool lzo/zbud
[ 1.656906] Btrfs loaded, crc32c=crc32c-generic
[ 1.671335] mmc1: new high speed MMC card at address 0001
[ 1.683516] mmcblk1: mmc1:0001 S10004 3.56 GiB
[ 1.691379] mmcblk1boot0: mmc1:0001 S10004 partition 1 4.00 MiB
[ 1.696288] Key type encrypted registered
[ 1.696316] AppArmor: AppArmor sha1 policy hashing enabled
[ 1.704154] mmcblk1boot1: mmc1:0001 S10004 partition 2 4.00 MiB
[ 1.706077] mmcblk1: p1
[ 1.853990] tda998x 0-0070: found TDA19988
[ 1.855626] tilcdc 4830e000.lcdc: bound 0-0070 (ops tda998x_ops)
[ 1.855649] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 1.855655] [drm] No driver support for vblank timestamp query.
[ 1.856048] tilcdc 4830e000.lcdc: No connectors reported connected with modes
[ 1.856070] [drm] Cannot find any crtc or sizes - going 1024x768
[ 1.864895] Console: switching to colour frame buffer device 128x48
[ 1.870197] tilcdc 4830e000.lcdc: fb0: frame buffer device
[ 1.893946] input: tps65217_pwr_but as /devices/platform/ocp/44e0b000.i2c/i2c-0/0-0024/tps65217-pwrbutton/input/input0
[ 1.894477] tps65217 0-0024: TPS65217 ID 0xe version 1.2
[ 1.894974] at24 0-0050: 32768 byte 24c256 EEPROM, writable, 1 bytes/write
[ 1.895176] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz
[ 1.896577] remoteproc remoteproc0: powering up wkup_m3
[ 1.897100] remoteproc remoteproc0: Booting fw image am335x-pm-firmware.elf, size 217148
[ 1.899495] remoteproc remoteproc0: remote processor wkup_m3 is now up
[ 1.899517] wkup_m3_ipc 44e11324.wkup_m3_ipc: CM3 Firmware Version = 0x192
[ 1.900317] asoc-simple-card sound: hdmi-hifi.0 <-> 48038000.mcasp mapping ok
[ 1.901993] PM: bootloader does not support rtc-only!
[ 1.902980] omap_rtc 44e3e000.rtc: setting system clock to 2000-01-01 00:00:00 UTC (946684800)
[ 1.902993] of_cfs_init
[ 1.903289] of_cfs_init: OK
[ 1.903853] PM: Hibernation image not present or could not be loaded.
[ 1.904001] ALSA device list:
[ 1.904010] #0: TI BeagleBone Black
[ 1.906223] Freeing unused kernel memory: 1024K
[ 5.079528] EXT4-fs (mmcblk1p1): INFO: recovery required on readonly filesystem
[ 5.079544] EXT4-fs (mmcblk1p1): write access will be enabled during recovery
[ 5.440086] EXT4-fs (mmcblk1p1): recovery complete
[ 5.441921] EXT4-fs (mmcblk1p1): mounted filesystem with ordered data mode. Opts: (null)
[ 5.866240] systemd[1]: System time before build time, advancing clock.
[ 5.927346] ip_tables: (C) 2000-2006 Netfilter Core Team
[ 5.968050] systemd[1]: systemd 232 running in system mode. (+PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD +IDN)
[ 5.968835] systemd[1]: Detected architecture arm.
[ 5.970124] systemd[1]: Set hostname to <beaglebone>.
[ 6.572726] systemd[1]: Reached target Swap.
[ 6.573885] systemd[1]: Listening on Journal Socket.
[ 6.574352] systemd[1]: Listening on udev Control Socket.
[ 6.576293] systemd[1]: Set up automount Arbitrary Executable File Formats File System Automount Point.
[ 6.576737] systemd[1]: Listening on Syslog Socket.
[ 6.577068] systemd[1]: Listening on udev Kernel Socket.
[ 6.578569] systemd[1]: Created slice User and Session Slice.
[ 7.316081] EXT4-fs (mmcblk1p1): re-mounted. Opts: errors=remount-ro
[ 8.052090] systemd-journald[303]: Received request to flush runtime journal from PID 1
[ 13.611005] nf_conntrack version 0.5.0 (8192 buckets, 32768 max)
[ 13.887939] random: crng init done
[ 14.915848] net eth0: initializing cpsw version 1.12 (0)
[ 14.915873] cpsw 4a100000.ethernet: initialized cpsw ale version 1.4
[ 14.915882] cpsw 4a100000.ethernet: ALE Table size 1024
[ 14.987874] SMSC LAN8710/LAN8720 4a101000.mdio:00: attached PHY driver [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=4a101000.mdio:00, irq=-1)
[ 15.037724] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 15.167223] using random self ethernet address
[ 15.167242] using random host ethernet address
[ 15.342085] using random self ethernet address
[ 15.342105] using random host ethernet address
[ 15.798134] Mass Storage Function, version: 2009/09/11
[ 15.798159] LUN: removable file: (no medium)
[ 16.199838] usb0: HOST MAC b0:d5:cc:fc:6d:f2
[ 16.201511] usb0: MAC b0:d5:cc:fc:6d:f3
[ 16.219612] usb1: HOST MAC b0:d5:cc:fc:6d:f5
[ 16.223913] usb1: MAC b0:d5:cc:fc:6d:f6
[ 16.643594] configfs-gadget gadget: high-speed config #1: c
[ 17.871443] IPv6: ADDRCONF(NETDEV_UP): usb1: link is not ready
[ 33.362334] ti-pruss 4a300000.pruss: creating PRU cores and other child platform devices
[ 33.557059] remoteproc remoteproc1: 4a334000.pru0 is available
[ 33.557185] pru-rproc 4a334000.pru0: PRU rproc node /ocp/pruss_soc_bus@4a326000/pruss@4a300000/pru@4a334000 probed successfully
[ 33.637626] remoteproc remoteproc2: 4a338000.pru1 is available
[ 33.637794] pru-rproc 4a338000.pru1: PRU rproc node /ocp/pruss_soc_bus@4a326000/pruss@4a300000/pru@4a338000 probed successfully
debian@beaglebone:~$ dmesg | grep UART
[ 0.000000] Kernel command line: console=ttyO0,115200n8 bone_capemgr.enable_partno=BB-UART1,BB-UART4 bone_capemgr.uboot_capemgr_enabled=1 root=/dev/mmcblk1p1 ro rootfstype=ext4 rootwait coherent_pool=1M net.ifnames=0 quiet
/dev/ttyO1 can be located as well
debian@beaglebone:/dev$ ls -a ttyO*
ttyO0 ttyO1 ttyO4
debian@beaglebone:/dev$ ls -l ttyO*
lrwxrwxrwx 1 root root 5 May 8 21:40 ttyO0 -> ttyS0
lrwxrwxrwx 1 root root 5 May 8 21:40 ttyO1 -> ttyS1
lrwxrwxrwx 1 root root 5 May 8 21:40 ttyO4 -> ttyS4