Arduino Drives A 600-Character Display

[Peterthinks] admits he’s no cabinet maker, so his projects use a lot of hot glue. He also admits he’s no video editor. However, his latest video uses some a MAX7219 to create a 600 character scrolling LED sign. You can see a video of the thing, below. Spoiler alert: not all characters are visible at once.

The heart of the project is a MAX7219 4-in-1 LED display that costs well under $10. The board has four LED arrays resulting in a display of 8×32 LEDs. The MAX7219 takes a 16-bit data word over a 10 MHz serial bus, so programming is pretty easy.

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This Week In Security: Robinhood, Apple Mail, ASLR, And More Windows 7

First off this week, a ransomware named Robinhood has a novel trick up its sleeve. The trick? Loading an old known-vulnerable signed driver, and then using a vulnerability in that driver to get a malicious kernel driver loaded.

A Gigabyte driver unintentionally exposed an interface that allows unfettered kernel level read and write access. Because it’s properly signed, Windows will happily load the driver. The ransomware code uses that interface to turn off the bit that enforces the loading of signed drivers only. From there, loading a malicious driver is trivial. Robinhood uses it’s kernel-level access to disable anti-virus applications before launching the data encryption.

This is a striking example of the weakness of binary signing without a mechanism to revoke those signatures. In an ideal world, once the vulnerability was found and an update released, the older, vulnerable driver would have its signature revoked.

The last Windows 7 Update For Real This Time, Maybe

More news in the ongoing saga of Windows 7/Server 2008 reaching end-of-life. KB4539602 was released this patch Tuesday, fixing the black background problem introduced in the last “final” round of updates. Surely that’s the last we’ll hear of this saga, right?

Not so fast. Apparently that patch has led to multiple Windows Server 2008 machines failing to boot after install. According to Microsoft, the problem is a missing previous patch that updates SHA-2 support. Continue reading “This Week In Security: Robinhood, Apple Mail, ASLR, And More Windows 7”

A Little Rewiring Teaches A Creality Ender 3 New Tricks

The Creality Ender 3 is part of the new wave of budget 3D printers, available for less than $250 from many online retailers. For the money, it’s hard to complain about the machine, and it’s more than suitable for anyone looking to get make their first steps into the world of FDM printing. But there’s certainly room for improvement, and as [Simon] shows in a recent blog post, a little effort can go a long way towards pushing this entry-level printer to the next level.

The first step was to replace the printer’s stepper drivers with something a bit more modern. Normally the Ender 3 uses common A4988 drivers, but [Simon] wanted to replace them with newer Trinamic drivers that offer quieter operation. Luckily, Trinamic makes a drop-in replacement for the A4988 that makes installation relatively easy. You’ll need to change out a few caps and remove some resistors from the board to make everyone play nice, but that shouldn’t pose a challenge to anyone who knows their way around a soldering iron.

Beyond quieter running steppers, the Trinamic TMC2208 drivers also offer direct UART control mode. Of course the Ender’s board was never designed for this, so the MCU doesn’t have enough free pins to establish serial communications with the three drivers (for the X, Y, and Z axes). But [Simon] realized if he sacrificed the SD card slot on the board, the six pins that would free on the controller could be cut and rewired to the driver’s UART pins.

Combined with the Klipper firmware, these relatively minor modifications allows him to experiment with printing at speeds far greater than what was possible before. Considering the kind of headaches that a ~$200 printer would have given you only a few years ago, it’s impressive what these new machines are capable of; even if it takes a few tweaks.

$200 Resin Printer Reviewed

[3DPrintFarm] got an early version of the Phrozen Sonic Mini resin printer. If you look at the video below, he was very impressed with its build quality and results. The price is reported to be $200, although we have seen it on some web sites for a bit more. The build quality does look good, although you have to admit, the motion mechanism on a resin printer is pretty simple, since you just need to move up and down.

The printer uses a monochrome LCD which allows it to cure layers very fast (apparently, monochrome panels pass more ultraviolet light through). The panel also has a higher-rated lifetime than color LCDs

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