v1.31 released

29/03/2014 20:37

E2B Version 1.31 has now been available for a few days and I have had no bugs reported so far.

Bug fixing on grub4dos v0.4.6a has been going well thanks to the developers.

  • 0.4.6a supports Joliet ISOs (+ a recent bug fix).

This means we can map and access files in Joliet ISOs (such as most Windows ISOs) which may be very useful. It also means we can access linux ISOs that do not support the RockRidge extension (though most are made with RockRidge+Joliet).

  • 0.4.6a also adds USB 2.0 native driver support.

The USB driver support will be great when it works properly. As you may know, Plop! is a BIOS-level USB 2.0 driver but it is read-only. It does not support sector writes to a USB drive. This means we cannot use it for E2B which needs to make permanent sector writes to the E2B USB drive files and partition table.

With the rd/wr USB 2.0 driver in grub4dos 0.4.6a, we can bypass buggy USB boot code used in some BIOSes and we could also use it like Plop! if placd on a CD

e.g. Some BIOSes, when booting from a USB HDD, cannot access sectors past 137GB due to a bug in their USB driver stack. So as long as the grldr file is within 137GB on the USB HDD, we can boot to grub4dos and then install the grub4dos USB 2.0 driver stack (with just a simple usb --init command!). Now we can access all the ISOs and other files on the USB HDD, even if they are outside the 137GB limit!

Another example: We can now boot from a CD that contains grub4dos 0.4.6a or Plop!, then chain-boot to our E2B USB drive which will run grub4dos 0.4.6a and load the rd/wr USB 2.0 drivers so we have full rd/wr access and E2B can work.

 

Unfortunately, the grub4dos USB 2.0 driver in 0.4.6a does not seem to work with as many USB controllers as Plop at the moment and it is difficult for the developers to fix the problem when they don't have the actual systems to test it on. For instance, Plop! will detect the USB ports on my Dell Inspiron 530, but 0.4.6a won't detect any USb devices. It also seems to be rather fussy about the state of hardware registers and often a 'warm' reboot results in non-detection of the USB drive but a 'cold' reboot (i.e. switch off + on) will work.

 

When grub4dos version 0.4.6a is stable enough, I would like to use it as the only version in E2B and not use 0.4.5c at all.

 

 

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