Serpent in ICE40, Part 2.

This article is a continuation of “Can the Serpent Cipher fit in the ICE40 FPGA?”.

Below is a revision of the forward S-box of Serpent from the previous article, with all of the S-Box equations rewritten in the same form, [...]

Can the Serpent Cipher fit in the ICE40 FPGA?

The question of whether the Serpent cipher could fit in a ICE40 FPGA was posed recently, and my first thought was: why not bake what appears to be the heaviest moving part, and see how many gates it requires? Then it will be possible to estimate whether the entire thing [...]

The Google H1 Fritz Chip.

Edit: Step-by-step replication instructions for the skeptical experimenter.

This article is a review of what I have been able to discover regarding the Google H1, aka Cr50, aka the “G Chip”, found in all Chromebooks of recent manufacture, including the Asus C101PA, my current candidate for a full delousing attempt.
To my knowledge, there has been no [...]

The secret of the “Debug Accessory Mode” Adapter.

The exact internals of Google’s proprietary “Suzy-Q” debugging device are, at the time of this writing, unknown.
However, I have found how to make an apparently-compatible device:

We connect the USB-C “business end” into a Asus C101PA machine; the USB-B end into a reasonable Linux PC, where we then:

echo 18d1 5014 > /sys/bus/usb-serial/drivers/generic/new_id

…and /dev/ttyUSB0 … 5 , [...]

Posted in: Cold Air, Hardware, NonLoper, SoftwareSucks by Stanislav No Comments

Open Problem: “Debug Accessory Mode” on the Asus C101PA

Edit #2: Aaaand it’s solved:

echo 18d1 5014 > /sys/bus/usb-serial/drivers/generic/new_id

triggers creation of /dev/ttyUSB0 … 5 , several of which spew console log…
Example spew on boot. (Looks like RK’s UART..?)

Edit: apparently they’re USB lines! When connected as D-/D+ through a USB B-connector, to a Linux box, we get a device that enumerates with this descriptor.

The Asus C101PA [...]

Open Problem: Forcing MaskROM Mode on the Asus C101PA

The Asus C101PA is based on a Rockchip RK3399. These have a “maskrom mode”, where if the SPI EEPROM is disabled, the chip will attempt to boot from other devices: first, NAND flash, then microSD, and then finally a USB debug mode where you can attach a A-A cable and use the rkflashtool utility to [...]

Wanted: Write-Once MicroSD Card !

Allegedly these exist! — though I have only been able to find them offered for sale by the railroad car.
For certain applications, nothing else will really suffice.
If any of my readers know of (or wish to become) a vendor offering, in (for starters) mid-three-digit quantities:

a) One Time Programmable MicroSD card
b) MicroSD card with a true [...]

Open Problem: Delousing the Asus C101PA.

Apr. 26 update: This article is obsolete, the pill — was found; if you have this machine, scroll to the end.

The Asus C101PA Chromebook is a very interesting device: it contains a Rockchip CPU, for which we already have a working deloused Gentoo; it also contains such marvels as a non-blobulous Marvell 802.11 card, a [...]

The Return of Phuctor!

I have the pleasure of informing my readers that…
Phuctor is back!

It — exactly as it was, but with a few minor fix-ups for browsing speed — now lives on a very spiffy 32-core Opteron at Pizarro, the ISP.

The WWW UI is already up; the factoring proper will resume later tonight.

“Rodenticide” with the Seiko DPU414 Tape Printer.

The Seiko DPU414 is a small (110mm paper tape, ~90mm printable width) thermal printer, similar to the type used with cash registers everywhere, but slightly wider. It is quite unremarkable apart from the fact that no thermal printer of similar or greater width appears to be widely available; and also for the price (typically around [...]

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