990 B
[x] double-check resistors and capacitors - can I do with fewer unique values? [x] double check sd card keep-out areas with datasheet [x] swap sda/scl i2c test points [x] Do we even need any pullup/down resistors?? can't the esp32 do this internally? (update: it can) [x] i2c Pins need reassigned so they match what is on the dev boards, which use 17/18 for the OLED display. Or we somehow also squeeze an OLED into the dev boards. Or maybe replace the OLED entirely with just some LEDs to indicate sensor state?
R2: [ ] some kind of power consumption measuring chip? INA233? [ ] protection diodes on usb lines? [ ] pull-down resistor before LED strip? [ ] CS line on SD card
R3: [ ] MP2662 lipoly charger chip on a 3.7v battery at 2500mAh [ ] redesign power supply to use a buck booster from the 3.7v battery to 5v for the display, and a simple divider directly off the battery for 3.3v for system power [ ] soldering ports to accept 3W at 6VAC to charge the battery from the bike dynamo