Thursday, June 16, 2016

arduino based multi-function display for Vanagon - part 2

I added a clock and calendar screen. It took a bit of work to sort out the navigation logic since this is a new feature that I didn't plan for. With each feature that I add, it had been a hand-to-hand combat to conserve precious memory, both the flash and the static RAM. The latter is most critical as there is only 2k bytes. My goal is to have a least uncommitted 512 bytes left. The power management features that I implemented is working very well now and appears to have few bugs. The joystick UI is very smooth without mis-registration. I also managed to add time stamps to the file creation and modified.

Tuesday, June 14, 2016

arduino based multi-function display for Vanagon - part 1

This is the continuation of a series of post staring with my purchase of an Arduino Uno microcontroller board. Started as a project in search of a mission soon it took on an evolution. It evolved into a project that fulfills some needs that I have long wanted to address and more.

a multi-function display for isolde - part 9

The keyword for this post is power management. Dealing with power management is complex work in hardware or software design. The algorithm of this Vanagon multi-function display has now becomes quite complex. There is a round robin multitasking in which the tasks has their independent cadence and conditional logic. Additionally there is timer interrupt driven polling of the joystick. Now I am adding power management features to manage the ability of soft-on and soft-off based upon the Vanagon's ignition, as well as the ability to use the data logger function independent of the Vanagon's ignition key position. I started to add the power management function when the flash memory is already at 95% capacity. The RAM is already at 70% capacity. Cutting it tight is an understatement.