Requirements Easily found when misplacedBig enough to hold easily but not too big that it's cumbersomeShould have a battery compartment so that unskilled personnel can replace batteries without having to open up the housingRoom enough for the necessary...
I modified Android application and Control Unit firmware so that front lights can also be controlled (brightness, blinking mode) via Bluetooth. Previously only rear lights settings were being sent from the phone. Now Control Unit receives all the settings...
The build of the module was pretty strait forward...with some complications. Except for one all footprints matched the parts I have. The LDO for VCC_USB was the wrong footprint, a SOT-89-3 should have been a SOT-223. I fixed this by soldering cables...
I wanted to connect replacement LCD to the original LCD connector, with no "ugly hacks" like interfacing with VGA connector and other workarounds. The original LCD used 9-bit TTL RGB interface (3 pins for red, 3 pins for green, 3 pins for red), which...
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,...
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...
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...
The STM32 board was just a hair bigger than the PIC, but the biggest pieces are still the power switch, channel button, & battery. The plan is just to print an L enclosure which scotch tapes around the hot shoe & sticks up. The antenna will...
PSRAM Challenges The PSRAM presented numerous challenges throughout development. One issue arose from the SSI clock divider, which could only be set to even integers. When the RP2040s were originally clocked at 266MHz to meet N64 SRAM timings and the...
I'm going to create a stand-alone PSoC project to use the PSoC to read SD cards. I'm going to start with the hardware defines for this project (which should leave the Z80 hardware pins unmolested) and just not download code. For the software piece, I...
See Update BelowContext being more that of the puzzle of cases not one case "to rule them all," but I digress. The past week I've been going through a few catalogs to find an enclosure for D-DAQ's mainboard. Previously, the PCB's form factor was based...
The ROP2 and ALU part has been slowly expanding to the SUXEN but the log 70. The nexus reminds that something is missing : I have forgotten to include PC+1 (NPC) value. So another level of MUX is required, which is fortunate because I had...
Hardware testing is complete on all the jump and branch instructions. So that's the first 8 out of 256 instructions tested! The next 24 are loading operands. These should work fine since the jump/branch instructions are also loading operands in order...