Page Comparison

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Date

Individual

Progress

June 28th

Aashmika

cleant up the mockup table for easier use and searching - please keep it this clean or cleaner!
Added all ESD mats, ground connections and wrist straps (did this last week but will add it here)
- Whenever testing on mockup or motor bench, please use the wrist-strap to minimize ESD effecting components
Found telemetry stuff including PoE module, bullet, rpi, gps/lte hat, antennas (all from MSXII besides gps hat which I picked up yesterday from James) → will go in later to set it up and see if the PoE module is working as it should

June 28th

Brandon

reflowed UV Cutoff board (ready for validation)

June 29th

Aashmika

set up the “telemetry mockup” after finding all the telemetry stuff used in MSXII. It is a “tapey” solution for now once i confirm everything is included as needed. Installed raspbian on one of the Pis from MSXII for the purposes of telemtry testing, not sure what else fw would like. TLDR: Turn on the supply and it should be good to go! The following briefly explains setup:
Set up the pi to interface over ethernet to the poe module that is connected to ubiquiti bullet. The power supply connects to a 12V breakout board from MSXII that supplies power to a 12V-5V OTS regulator meant for car usage, that with some barrel jacks in between powers the pi (i had to sacrifice the usb B end of a usb to microusb connector for the easier powering option). HDMI from pi to monitor and logi unifying device for mouse and keyboard on USB port. GPS+LTE hat on top of the rpi connected with usb-microusb. The ubiquity bullet has an antenna, the rpi hat has a connector for gps and lte to either antenna (note: do not unplug the connector too much it is a fragile board connector and can survive very few connector cycling). Finally I just connected the peak-can dongle cuz there was one in the MSXII telemetry components.
tested ps for main rails when supplied with the power supply input, and saw that it maintained a output 13.5V to front pd! this means jump start definitely works, but need to check if the cell is disconnected once the output is maintained. Did not see any shorts, and did not try any other inputs. Will check all this once I start load testing

June 29th

Brandon

finished soldering remaining components for Center Console board (ready for validation)

July 3rd

Jess + Aashmika

POWER DISTRIBUTION

checked fan control front curve by forcing the new rear rev to be front
works but range is limited from 0-49 (just printing fan speed)
checked physically by slow-mo filming the fan lol, you can see the different speeds

POWER SELECTION

small bug: not initializing the adc pin for 3v3 cell sense Hewitt McGaughey
printing doesn't work very well with the PRI etc etc formatters on ARM Hewitt McGaughey

Code Block

[0] projects/power_select/src/power_select.c:115: Voltage hu: 0 mV
[0] projects/power_select/src/power_select.c:115: Voltage hu: 1 mV
[0] projects/power_select/src/power_select.c:115: Voltage hu: 2 mV
[0] projects/power_select/src/power_select.c:153: Current hu: 0 mA
[0] projects/power_select/src/power_select.c:153: Current hu: 1 mA
[0] projects/power_select/src/power_select.c:153: Current hu: 2 mA
[0] projects/power_select/src/power_select.c:126: Temp hu: 0 C
[0] projects/power_select/src/power_select.c:126: Temp hu: 1 C

with fix in place, still gives wrong input
powering from aux constantly power cycles the controller board?? no good
swapped the big LT4417 with the old power selection
may have fried parts of it by putting it on backwards (may it rest in peace)
Continued after jess left:
- Replaced the LTC4417 once again, but found that the power supplies would be turned on and connected but still would either cycle the board or make loud sizzling sounds
- Probing the 3V3 rails when the power supplies were off resulted in around 2.5V being recorded, which was weird since by itself the cell was 3.3V. The 3V3 rails on the board itself also probed to about 1V with some randomness that might be attributed to the probes being used at the time
- took out the cell and tried again without it connected, and the power path switching started to work consistently with all three power supplies! Not sure why this worked talked with Nita who found this in the block diagram of the LTC4417, which shows it might get temporarily powered through the V1-V3 and might get enabled through the following
- The sequence for how it turns on almost seems like an inbuilt turn on function, in which when one of the power supplies is turned on, the vbat on the output turns on, then off (briefly) then on again for the rest of the duration of the board getting power. I took pictures of the scope with the following images:
- Image RemovedImage Added
  Nita will be helping me look through the datasheet to see if this is an intentional possibility. From those consistent waveforms, it seems like this is being done by the IC and not due to surge or any transients.
- there is still some issue when I turn on the aux power supply in which the vbat starts to turn off and on repeatedly and not hold vbat steady. This makes me believe that there might be a transient cuasing the vbat line to go high temporarily and for it to hold the timing has to work with a high pulse to enable the IC for the right amount of time before connecting an input.
- One thing to note is that this behaviour although not well documented was observed with the previous revision of power select, and was kind of used but not looked into so that it could be incorporated with the rest of the mockup table to give power to other boards.