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This post lists the commands to erase, and W95 FAT32 (LBA) format an SD card so you can boot Linux from it on a ZCU102, ZC702, or other embedded system. These instructions will fix the boot process failing as indicated by red PS_ERROR_OUT and INIT_B LEDs and the BootROM failing with the error, "0x3B - Reading failed from the selected boot device." The SD card boot switches for a ZCU102 are also listed below. To ensure you're successful.
Note: these steps will erase all the data on the SD card you use.
Step #1: Plugin your SD card
Step #2: Type dmesg to find the device name:
dmesg
At the end of the output you should see something like:
[4631534.438306] sd 33:0:0:1: [sdc] 31116288 512-byte logical blocks: (15.9 GB/14.8 GiB)
[4631534.452427] sdc: sdc1
[4631534.973011] FAT-fs (sdc1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
Step #3: Zero the SD card
This is optional
Type:
sudo dd status=progress if=/dev/zero of=/dev/sdc bs=4096
Note: this will take a little bit
Note 2: without bs=4096 I got 6.3 MB/s, with it I got 50-100 MB/s
I saw this once my invocation completed:
15927132160 bytes (16 GB, 15 GiB) copied, 1248 s, 12.8 MB/s
dd: error writing '/dev/sdc': No space left on device
3889537+0 records in
3889536+0 records out
15931539456 bytes (16 GB, 15 GiB) copied, 1248.48 s, 12.8 MB/s
Step #4: Add a partition table. Type:
sudo fdisk /dev/sdc
Step #5: Use the responses in bold
Welcome to fdisk (util-linux 2.27.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0x7c06933e.
Command (m for help): m
Help:
DOS (MBR)
a toggle a bootable flag
b edit nested BSD disklabel
c toggle the dos compatibility flag
Generic
d delete a partition
F list free unpartitioned space
l list known partition types
n add a new partition
p print the partition table
t change a partition type
v verify the partition table
i print information about a partition
Misc
m print this menu
u change display/entry units
x extra functionality (experts only)
Script
I load disk layout from sfdisk script file
O dump disk layout to sfdisk script file
Save & Exit
w write table to disk and exit
q quit without saving changes
Create a new label
g create a new empty GPT partition table
G create a new empty SGI (IRIX) partition table
o create a new empty DOS partition table
s create a new empty Sun partition table
Command (m for help): o
Created a new DOS disklabel with disk identifier 0x138cb35c.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): <Enter>
Partition number (1-4, default 1): <Enter>
First sector (1-2047, default 1): <Enter>
Last sector, +sectors or +size{K,M,G,T,P} (1-2047, default 2047): <Enter>
Created a new partition 1 of type 'Linux' and of size 1023.5 KiB.
Command (m for help): t
Selected partition 1
Partition type (type L to list all types): L
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden or c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi ea Rufus alignment
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD eb BeOS fs
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ee GPT
10 OPUS 55 EZ-Drive a7 NeXTSTEP ef EFI (FAT-12/16/
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f0 Linux/PA-RISC b
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f1 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f4 SpeedStor
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ f2 DOS secondary
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fb VMware VMFS
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fc VMware VMKCORE
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fd Linux raid auto
1c Hidden W95 FAT3 75 PC/IX bc Acronis FAT32 L fe LANstep
1e Hidden W95 FAT1 80 Old Minix be Solaris boot ff BBT
Partition type (type L to list all types): c
Changed type of partition 'Linux' to 'W95 FAT32 (LBA)'.
Command (m for help): w
The partition table has been altered.
Syncing disks.
Possible Error
If you see:
Re-reading the partition table failed.: Device or resource busy
The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).
Type:
umount /dev/sdc1
…and try fdisk again
Note
You can also type in a script:
(echo o; echo n; echo; echo; echo; echo; echo t; echo c; echo w) | sudo fdisk /dev/sdc
or
(echo -e 'o\nn\n\n\n\n\nt\nc\nw\n') | sudo fdisk /dev/sdc
Step #6: Type:
sudo mkfs.vfat /dev/sdc1
You should see something like:
mkfs.fat 3.0.28 (2015-05-16)
Step #7: Type:
mkdir sdcard_part1
sudo mount -t vfat /dev/sdc1 sdcard_part1 -o rw,uid=$(id -u),gid=$(id -g)
cd sdcard_part1
echo "Hello, World!" > test.txt
cd ..
sudo umount sdcard_part1
rm -rf sdcard_part1
To boot from an SD card on a ZCU102, set SW6 to SD1 LS:
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References
Good dd usage links [link]
Create a FAT file system image on Linux [link]
Re-reading the partition table failed with error 16: Device or resource busy [link]
How to create and format a partition using a bash script? [link]
Pictures of SW6 for every ZCU102 Zynq UltraScale+ MPSoC Boot Mode [link]
Xilinx logo from [link]