So before I put through a $400 PCB order, I wanted to "pre-test" a few of the circuit designs that I put into the NIM-1. It's simple things, but I want to make sure that everything will work "the way I think it will" before making such a commitment and investment. This also forces advancement of the VDAC firmware, which will form the heart of the NIM-1. I am also pretty excited to "announce" that I may have found a way to incorporate OWI code into VDAC in such a way that the other OBD types will not get starved for attention and potentially miss important updates.
The first update to the VDAC firmware will actually be a pretty major one; implementation of what I've been calling the "Multi-Drop Firmware" to allow the creation and deployment of [smaller|purpose-built|multiple] VDAC boards together on the same 4-wire bus (GND, +12VDC, RS485A, RS485B). I wrestled back and forth with the idea of making every single device Ethernet / WiFi enabled, and that is still an option where the application warrants it, but there are certainly places throughout my house where it makes far more sense to simply run a 4-wire bus between multiple modules all tied back to a single NIM or even directly into a USB port or 485-Ethernet/WiFi adapter.
I've ordered quite a few parts from China today to begin testing specific circuits that form the NIM-1. My goal is to prove each circuit before the PCB run as it is quite expense and I've already caught a number of glitches / mistakes / omissions / problems through this process. It may even inspire me to add support for a number of other devices via pin headers for future expansion or user options. One such idea is the incorporation of a display port, for something like a 2x16 or 4x20 LCD display, or maybe even something simpler like one of those TM1638-based LED/Button interfaces; the possibilities are endless. I love this stuff!