A laptop keyboard is a diode-less key matrix. Its keys are distributed in a way that you can press the most important key combinations at once, despite the lack of diodes - to the point where some rows only contain one or two keys. Often, there's also...
This code is a slight update of the last one, updated:>Better Uptime Counter>LCD Shield>New Pin out Diagram>Restart Protected Calibration Details>EU and US Plug Calibrated Probe Also a quick update to the code so the calibration value will survive a...
An article recently published on MOONGIFT, a Japanese developer site, has showcased RasDash! The article is entirely in Japanese and Google Translate won't accept the URL as it has special characters but YANDEX does. Below are some links and a basic...
They say that a picture is worth a thousand words, so: As you can see, THE NEW PEAK DETECT CIRCUIT WORKS! It's always nice to see something work in real life versus simulation. It's kind of hard to see exactly how close the peak detect output...
Just a quick picture to show off the tremendous root growth. The plants are about 5 weeks old except the one on the bottom of the frame which is six weeks old. Click on the picture and zoom in to get a good view of how dense the roots are.You...
Redford did a whole lotta work reverse engineering the BIOS code and figured out that most of the interesting stuff (password check, challenge/response for lost password) is actually done by something off the main x86 processor. We figured out that it's...
Operating under the current assumption that RAM is 32 KiB banked at address 0000-7fff, with the first 256 bytes masked off by special function registers and internal SRAM, some other code sections of interest were found. E.g.:ED00 loc_ED00: ED00...
One of my motivations is to also get it to work on my 8085 SBC. It turns out to be fairly straightforward. I have a hacked asz80 that flags instructions that are not in the 8080 subset. Here is the output of a grep '^[a-z]' efz80.lst a 0105 ED 79 [12]...
This represents a complete OPCODE list with 14 Constants (int values) available and 10 Labels (byte values) available for creating subroutines. Constants were favored over Labels, but this is up for evaluation. NOP and HCF were both added to the official...
I might be missing a few connections yet which I'll correct as I come across them, but here is the pinout of the XC3S250E FPGA on the control board. Note that the SRAM and the Flash share an interface bus. Also note that the JTAG interface...
Previously, while rummaging for scan codes, I was correlating known behaviour with key codes. One of those keys was the Clear File key (0x56). I forgot to post about that find, but it's still worthwhile to mention the file clearing operation...