Time for a new entry to show I am still working on this project. I intended to add this log entry three days ago when I realized it had been 9 days since my last project log but I got side-tracked with other activities.

I've been working on the software for the microcontroller. I have much of the overall framework worked out and some of the routines already coded. I've made some changes based on the limited RAM in an ATtiny45. I originally needed two buffers totalling 255 bytes but, with only 256 bytes of RAM available, that just wasn't going to work. I'm going to restrict the moving average to use a maximum of four locations. I only need buffer space for three locations as the fourth is in the buffer holding the current GPS position data. I'm also packing multiple bits of information in a couple of bytes. This has saved 11 bytes but I have to watch the use of local variables and leave some room for the program stack and interrupt handlers. It is always fun working with microcontrollers with limited memory. It forces you to get creative.

In a previous log entry I said I was taking a break from working on 3D models. I mostly did but I still spent a little time on some 3D models for use with Kicad. I have ordered some right-angle pushbuttons. I have a diagram showing different views of the part so I can start on a 3D model and footprint while I wait for them to arrive.

I've also done a bit more work on the PCB layout. I haven't finalized the positions of all the parts yet. I still need to source a right-angle slide switch with a long enough handle. The user will need to be able slide the switch when when the interface board is in its final enclosure. Additional changes may be required to the PCB once I have the final footprints for these two parts.