Notes on using DS3245SG 45kg 270 degree digital servo from Amazon

https://www.amazon.com/ZOSKAY-Torque-Coreless-Digital-Stainless/dp/B0CN6J4TCR

I couldn't find a lot of data online for this servo, so here is what I found:

1. I needed the full 270 degree range to fully turn a cube side.  But mechanical mounting meant a side was
mounted slightly off.  The mount was epoxy so I couldn't adjust it that way.

Turned out the servo works outside the range 500-2500ms.  I had to modify the esp32servo code so it would send
PWM outside that range, but the servo was happy to move outside the specified range.

I did not measure what the actual range is.

2. When one servo is turning I want the other servos to freewheel (backdrive).
This way if the alignment is slightly off, the cube will turn the other sides slightly and not bind.

If PWM is held low and power is turned on, DS3245SG servo will freewheel (this is what I want).

After power and PWM is applied, if you then hold PWM low, DS3245SG servo will hold in last position.
(This is what I don't want)

So I power cycle for each turn, and hold all other PWM signals low so the other servo's freewheel.

3. I was getting inconsistent turn times from servo power up.  The delay from power up to turn was noticable.

This was fixed by turning on PWM, delaying 200ms, and then powering up servo.