On the R-Time 8 aspect I changed to a larger battery same as was used on the original ICD variant back in the day (CR2430). I also have the power for this and the SDrive as an 'Always ON' situation taken from the 576NUC+ 5V Stand-By power connection, which is available from the internal SIO header. This means that so long as the NUC is plugged into wall power, irrelevant of whether the 576NUC+ is turned on, the R-Time 8 will run from the 5V power supply and not from its battery thus greatly extending the battery life. I wouldn't be surprised if the battery lasts for at least a decade with this setup.
Because the SDrive also gets its power in a similar aspect, drive assignments should be retained between power cycles.
Over the next couple of days I'll be double checking the PCB layout and schematics, and if all looks solid I'll be pressing the BUY button at JLCPCB soon after. Then when those sample boards arrive we'll see how or if I screwed up on something - always exciting.
Update 9/13/2023: I never pressed the buy button on this board version. After running some breadboard tests, and because of discussions in the A8Pico Cart AtariAge thread about protection circuits, and a change in direction on the SDrive aspect, everything changed. So much so, that an entirely different PCB layout was required, with the first sample PCB based upon this change having now been manufactured and awaiting assembly and test.
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