Well, I should have expected the Fibonacci code to work since I already checked out all the previous functions of it. So I'm wondering what isn't going to be working to prevent the ROM code from working. I'm running the ROM v3 code because...
I have continued debugging the hardware mock-up. The fundamental target was to program a simple RPN calculator UI with 6 operations plus a number of scientific functions. The integration with BASIC will come later, after all the hardware components are...
There are two ways to get to the Z80 bus for external operations. RESET* - Clears PC and sets address/data bus to Hi-ZBUSREQ* - input - Address, Data, MREQ*, IORQ*, RD*, WR* to HiZBUSACK* - output indicates that BUSREQ* signal was performed (Hi-Z busses)...
[This post brings me up to date with the work I've done so far, and corresponds to the state in commit 0e4b928083ae69bb6ae577197ac016e93a77e80e] I've documented my design for the NEXT routines, which I've committed to Github here. It's a little sketchy,...
I promised this log for several times and now it is finally here. Let's start with how a rising edge looks.RisetimeThe orange and light blue ones were measured using commercial devices, the Agilent 86100C and LeCroy WaveRunner (this one was already mentioned...
I should apply a gamma curve to the analog axes read from Classic controller to make the response of the stick more subtle near the center and more steep close to the edges. Classic controller analog sticks provide position information with...
Version 1 of the hardware arrived, and I have been testing it. Almost immediately, I discovered I had made a connection mistake on the 3.3V regulator, and the system would not run normally from battery power. I desoldered that part, and by providing...
When you search google for FAT file format you get tons of pages on formatting disks. It's harder to pull out the detailed format of the SD card. Wikipedia to the rescue (Design of the FAT file system). A less technical FAT32 Wikipedia page is File...
MethodThe idea is simple, just build the SDK in normal Dual Core configuration, but pin all tasks to the first core. We then can run a task on the second core which should (in theory) run uninterrupted by everything.But: We can't be sure nothing is running...
lBefore I can get my hands on more numbers from the scan, let's go back to 147. C-ving. For the prime 1511 and higher, there is not enough data to get a complete histogram and there are histograms with 3 holes. We already know that the holes are symmetric...
A powerfull dev board with the ESPRESSIF™ ESP32-S2®, a high resolution display, a RGB LED, a battery charger and a bunch of GPIOs. There are many ESP32 board on the market but very few with the new ESP32-S2 which handles USB communications, new...
You can use the ESP32 simulator on Linux, Windows or even Chromebooks! The project runs on the browser. So, you can always run the projects on mobile as well! There are several users using the ESP32 simulator on their MacOS as well! The connection diagram...
The 5.21E ROM works file with the current board, but the 7.11A ROM uses a different pin for the vertical sync signal. This can be fixed, but then the 5.21E ROM results in no display. Rather than fixing the hardware (with a jumper to be changed when the...
Project choices and the mission As stated in the summary, my goal is to provide an open solution to the bipedal walking problem, in order to give others a starting point and source of inspiration. This includes hardware designs, drawings, assembly plans,...
I'd been pushing hard trying to get a demo of how you can break an AES-256 bootloader. This type of bootloader is often used in products for protecting firmware updates and a good demonstration of why you should care about side channel attacks as an...