I'm planning on making a bootable USB, but first I have some questions regarding it, you can answer any of the questions you like.
Can a bootable USB access a hard drive where windows is installed on without password?
What is the safest OS for a bootable USB?
Which OS is the freeest (as in editing the source code and such)
If you create and boot the system from a USB is not much different from normal one, the only difference is in kernel, on hardware abstraction layer (this is handled by OS) and data transfer speed.
Yes, as long as the OS from USB have SATA (or whatever you have) driver and accept your HDD partitions format (NTFS/EXT etc). It doesn't matter if you have or not password but to have the data unencrypted. (usually user personal's folders are encrypted).
Safest.. no one is safer than another.
Mainly any Linux distribution.
I will recommend Ubuntu because it have the biggest community.
Related
I would like to use a windows machine as a USB488/USBTMC device. USB488/USBTMC is a reimplementation of the good old GPIB/IEEE-488 on USB rails. But most articles on the topic refer to a Windows machine as a host/controller. The Windows USB stack is not well suited for USB device/USB OTG modes. However, if you look at some of the high-end gear like oscilloscopes and spectrum/network analyzers, it is well known that they are often Windows machines inside with some additional hardware. So, how it is done?
To some background: it is a project to retrofit a very old SEM microscope with new hardware. The current one is a 68k custom system with a CRT that uses a GPIB interface for comm with a PC. Things like sample spectroscopy are done as a BASIC program running on a pc and communicating through that gpib port. The plan is to replace that 68k junk with a modern day windows pc with an FPGA on a PCIe bus. For compatibility reasons, it would be nice to have a usb488 port in the new PC. Though I have no idea of how to do it properly. The only solution I have so far is to have some cheap USB-capable micro hanging on the SPI bus on the FPGA facing side and a USBTDM class on the USB side. But maybe Im missing something and there is a specific thing or chip that exists that can do it that Im not aware of.
I can only speculate how high-end oscilloscopes achieve it. The most likely option is that they use a dedicated chip like a MAX3420E. It is connected via SPI. Part of the USB protocol is implemented by the chip, part of it will be implemented by the oscilloscope software.
Most USB controllers chips found in PCs can operate as the host only. And even if they could do a role swap, Windows (for Desktop) has not supported device/peripheral mode until recently. It now does. See USB Dual Role Driver Stack Architecture. But I don't fully understand it to tell you what hardware you would need to purchase where this feature is enabled.
Role swapping is very common on smartphones. It is also implemented in Linux (search for "Linux USB gadget"). Many Apple Macs can run in Target Disk Mode, which is a USB device/peripheral mode as well.
I know how to change boot order through bios settings, but I have a unique situation where doing it programatically would be better. The company I work for sells and supports software remotely to thousands of non tech savvy customers. We can't touch their hardware settings, we are only the software vendor.
Recently we rolled out a option for their PCI compliancy that requires a separate removable drive to store a private encryption key. Customers that use this option have to leave a usb drive with a .dat file containing the RSA key at all times. Currently this presents an issue when customers reboot. Sometimes we can walk them through over the phone how to change their bios settings to skip the USB drive, but in many circumstances we cannot, because of the caller and the other end of the phone not being tech savvy enough to change bios settings, and different PC's having different BIOS setups.
So my question is, is there any kind of ini file I can create or boot record on the disk itself than can be added or changed to cause the system to see that there is no OS on the USB, keep going down the list of boot drives. Instead, with no OS many PC's hang on Missing OS screen until we have customer remove drive reboot and plug back in after Windows starts to load. All PC's are Windows, all XP or newer.
You're talking about manipulating BIOS Setup data. Unfortunately there is no industry-standard for computers to manipulate Setup fields, like the boot sequence, so any solution is likely to be vendor-specific.
An example: Dell Inc. provides customers OpenManage Client Instrumentation (OMCI) that allows admins to remotely change settings, like boot sequence, via standard interfaces like CIM/WMI. See this whitepaper:
http://www.dell.com/downloads/global/solutions/omci_info.pdf
Especially:
OMCI is the Dell instrumentation package that enables OptiPlex™, Dell
Precision™, and Latitude™ systems to be managed remotely. OMCI
contains the underlying driver set that collects system information
from a number of different sources on the client computer, including
the BIOS, CMOS, System Management BIOS (SMBIOS), System Management
Interface (SMI), operating system, APIs, DLLs, and registry settings.
OMCI exposes that information through the CIMOM interface of the WMI
stack. Thus, OMCI enables IT administrators to remotely collect asset
information, modify CMOS settings, ...
OMCI is specific to the Dell BIOS, so it won't work with other vendors' machines. Other enterprise hardware vendors (e.g. HP, IBM) provide similar software. If you can live with a vendor-specific solution, this may work for you.
May I ask if your USB is actually non-bootable?
How did you format it? FAT32, NTFS etc?
Why can't Windows bypass this usb when booting normally when (i assume) it is not bootable. Normally my system boots to Windows OS even if there is a non-bootable usb plugged in.
BTW have you tried keeping the DAT file on usb as hidden, read only, it's worth a try.
We are developing an embedded system which will use a PC motherboard running Linux or Windows Embedded (have not decided which one). The board will read data from FPGA via PCI Express.
Novice question: do we have to develop our own PCIe driver or we can use something from the operating system? If we need our own, can you recommend a resource?
It really depends on what kind of data you want to transfer with the device. If you just want register read/write you could just mmap /dev/mem and have a user space driver.
If you need to do DMA or interrupt then you'd likely have to write your custom driver.
Yes, unless your device corresponds to a standard device profile, you will need a custom device driver. Because you have not selected your operating system yet, your question about resources is pretty wide open still since obviously the OS selection directly affects driver design. For Windows you probably want to start here. Under Linux, perhaps here.
Is there anyway that you can expose local partition or disk image through your computer usb to another computer to appear like external drive on mac/linux/bsd system ?
I'm trying to play with something like kernel development and I need one system for compiling and other for restarting/testing.
With USB: Not a chance. USB is unidirectional, and your development system has no way of emulating a mass storage device, or any kind of other USB device.
With Firewire: Theoretically. (This is what Apple's target disk mode is using.) However, I can't find a readily available solution for that.
I'd advice you to try either virtualization or network boot. VirtualBox is free and open software, and has a variety of command line options, which means it can be scripted. Network boot takes a little effort to set up, but can work really well.
Yet another option, is to use a minimal Linux distribution as a bootstrap which sets up the environment you want, and then uses kexec to launch your kernel, possibly with GRUB as an intermediary step.
What kind of kernel are you fiddling with? If it's your own code, will the kernel operate in real or protected mode? Do you strictly need disk access, or do you just want to boot the actual kernel?
I have been tasked with writing a USB driver for our embedded software to send raw data to Host. This will be used to send some logging data to host. We are using iMX31 litekit for development.
From the documents that I have read on USB, my understanding is that the embedded device will be in device mode only. Also it will only be communicating with host machine.
So can any one guide me here? Any article, reference or code is welcome.
Some things to consider:
Is this a high bandwidth device like a camera or data recorder, or a low bandwidth device?
For low bandwidth, I would strongly consider making your device act as a USB HID class. This is the device class that supports keyboards, mice, joysticks, gamepads, and the like. It is relatively easy to send data to nearly any application, and it generally doesn't require that you write a custom device driver on the host side. That latter feature alone is often worth the cost of lightly contorting your data into the shape assumed by the HID class. All the desktop operating systems that do USB can use HID devices, so you get broad compatibility fairly easily.
For high bandwidth, you would still be better served if your device fits one of the well established device classes, where a stock device driver on the host end of the wire can be used. One approach that often works is to use the Mass Storage class, and emulate a disk drive containing one file. Then, your device simply mounts on the host as if it were a disk, and you communicate by reading and writing to one (or a few) file.
I would expect there to be a fair amount of sample code out there for any serious USB device chipset that implements either or both of HID and Mass Storage.
If you really must wander into fully custom device territory, then you will need to be building device drivers for each host platform. The open source libusb library can be of some help, if its license is compatible with your project. There are also ways in newer versions of Windows to develop USB drivers that run in user mode using the User Mode Driver Framework that have many of the same advantages of libusb, but are not portable off the Windows platform.
The last custom device I worked on was based on a Cypress device, and we were able to ship their driver and an associated DLL to make our application code easier to build. I don't know off the cuff if there is any equivalent available for your device.
For a really good overview, I recommend the USB FAQ, and the latest edition of Jan's book, USB Complete.