Skip to main content

ESPCLOCK4 - Implementation

I have uploaded the final code for ESPCLOCK4 to GitHub. Full details and schematic at the repository.

I have also created 2 prototypes, 25cm and 38cm clocks: 





I am quite happy with this version. It is much easier to debug (by using a dev board with the UART intact during development, and switching to one with the UART removed to save power for production), and very straightforward to implement on a prototype board. It also uses very few external components, but is equally power efficient.

Future enhancements will include:

- Adding an external clock crystal to eliminate the RTC_SLOW_CLK drift.

- Using C to write the ULP code. Assembly code is tedious and error-prone.

Comments

  1. Have you seen the recentish wifi clock movements from china? I think someone at a movement manufacturer might've been following your work ;)

    ReplyDelete
    Replies
    1. No I haven't! Must have been a recent development. At ~$75 for the 12-inch model, it's a little too rich for my taste. I will hunt around for reviews and try to figure out how it works. Very interesting! Thanks for the info.

      Delete
    2. Preliminary research shows:

      1) WiFi clock movement uses 2 x AA alkaline
      2) Claimed battery life of 1 year
      3) Uses sweeping clock movement
      4) Synchronizes once a day
      5) Stops at midnight every day to preserve battery life, and restart next morning. Can be changed through web interface.
      6) Connects to NTP for network time

      Delete
    3. Yeah they're about $28 here out of the bay, I got one on the way just to see how it works. But your new 4 design is probably gonna work better. Out of interest why did you stop doing NTP queries?

      Delete
    4. NTP is the easy part, since that just gives you the UTC time. You still need to convert it to local time based on your timezone, and _that_ is the big hairy monster. No easier way then to outsource this task to a machine running a full OS that takes care of NTP + TZDB + DST info all in one place.

      Delete

Post a Comment

Popular posts from this blog

Update: Line adapter for Ozito Blade Trimmer

Update (Dec 2021): If you access to a 3D printer, I would now recommend this solution , which makes it super easy to replace the trimmer line. I have been using it for a few months now with zero issue.

Line adapter for Ozito Blade Trimmer

This is an adapter for Ozito 18V battery trimmer (and possibly some Bosch trimmers as well) that uses a plastic blade for cutting. It lets you insert a 2.4mm trimmer line (about 8cm long) and use that for cutting. Simply cut a length of trimmer line and briefly heat up one end with a lighter so that a little bulb is formed. Then insert the trimmer line into the adapter and slot that into the trimmer as per normal. Make sure the trimmer line is not so long that it touches the safety guard. If that is the case, simply trim off any excess with a cutter or scissors. This part is best printed using PETG, which is a tougher and more flexible material. PLA is more rigid and breaks more easily. However, even with PETG, it will still break when it hits something really hard. Since this takes only 0.5m of material and 15 minutes to print, I will usually print a batch of nine at a time at very little cost. The blades that they sell do not break when it hits a hard object, but ...

Cooling mod for the X96 Air

I realized after my Ugoos box died that overheating is a big problem with cheap Android TV boxes. A teardown of the Ugoos box shows that it does not have any heatsink or fan at all!  The X96 Air does have a heatsink, but the heatsink is located at the bottom of the casing with no ventilation. In this default configuration, with the ambient room temperature at 25c and playing a 1080p video, I was seeing the CPU temperature at 67c. I drilled a couple of holes at the bottom of the casing. The CPU temperature fell to 59c with the box raised about 2cm with plastic blocks. I retrieved an old 5V laptop fan: Then cut and strip away a spare USB cable: Solder the red and black wires on the fan and the cable: Secure the fan to the bottom of the casing with double-sided tape, then plug the fan into the box's USB connector. Here's a view of the box with some 3D-printed risers installed at the bottom to give the mounted fan sufficient clearance: The CPU now runs at 43c, a huge drop from the ...