Firmware on github

A project log for Solar MPPT Charger for 24/7 "IOT" devices

An inexpensive charge controller and 2A 5V power supply designed to supply remote power for devices ranging from Arduino to Pi 3 class.

Dan JulioDan Julio 08/31/2019 at 17:170 Comments

New Feature

With firmware v1.2, the watchdog functionality has been extended to allow a new capability.  A new 16-bit unsigned register called WDPWROFF is added that controls the length of time power is disabled when the watchdog timer expires.  It specifies time in units of seconds allowing power to be disabled for up to 65535 seconds (18 hours, 12 minutes, 15 seconds).  This means that the watchdog function can also be used to switch off power for a period of time, for example to turn off the user's system overnight.  The default value of WDPWROFF is 10 seconds like the previous firmware versions and the default value is restored every time the watchdog timer expires or is disabled.

Documentation and the arduino library have been updated.

Firmware Release

The v1.2 firmware source has also been uploaded to github.  This is the intended production release code.  I used Silicon Lab's Simplicity Studio as the IDE and compilation environment.  This code runs on the EFM8SB10F8 micro-controller and currently requires 7904 bytes (almost full!) and uses 140 bytes of xdata memory and 86.1 bytes of data memory.

Campaign Status

The Crowd Supply campaign is almost finished.  The parts are in China but unfortunately being held in customs.  My Contract Manufacturer is attempting to get them released.  I am exploring some options in case this becomes a long-term problem.