Tuesday, August 23, 2016
It was only in 2014 my Windows desktop computer went kaputt. I managed to diagnosed to the system power supply, or as I thought but the root cause was not entirely clear even though I managed to repaired it. I swapped out the power supply with another PC that has an identical unit. Strangely the donor PC works just fine with the "bad" power supply. That left me wonder if the power supply as after all not the cause of the failure. Fast forward to a few weeks ago, my same Windows computer died all a sudden while resuming from sleep.
Monday, August 22, 2016
It has been nearly a year since I decided to buy a 4-stroke leave blower against the common wisdom. Upon first receiving it I was very pleased with its performance, and especially how quiet it is. Even at full throttle I find it no need to wear any hearing protection. The other benefits are the cleaner exhaust and without having to deal with gasoline and oil mixture. I was also very impressed on how little fuel it consumes - until a few months into the ownership.
Sunday, August 21, 2016
I managed to maintained the upholstery in Isolde in pristine condition after 27 years. The secret is a layer of sacrificial material over the factory fabric. In recent years the fabric on the bed cover deteriorated and I have been challenged as what to do. The cover is a old fashion sleeping bag that has been modified in circa 26 years ago. Today these old fashion sleeping bags are few and far in between. I entertained replacing the worn fabric while keeping the insulation core of the sleeping bag. The problem is the retail cost of the fabric would cost more than the sleeping bag.
Friday, August 19, 2016
As in any design development, there are challenges with the parts that one specified. I happened upon the DHT11 temperature and humidity sensor because of its dual function. It would turn out it was fun while the curiosity lasted. I have 3 of this and found that they are worthless junk. The temperature reading often jumps around 2 degrees, and at time 8 in consecutive samples. Also all three are extremely inaccurate. I had play with the Maxim DS18B20 quite early on and found them to be very accurate for solid state active sensor. One reason reason that I didn't choose it was my attracted to the DHT11's humidity capability. The bigger reason is the library for the DS18B20 is very memory intensive, and I had ran out of program memory as well as SRAM.
Thursday, July 7, 2016
Recently I have been into making Japanese rolled omelette. Actually more like my interpretation of this omelette technique. I am inspired by how Japanese would take foreign dishes and turn them into their own versions of Western dishes but suit their taste.
Tuesday, June 28, 2016
Thursday, June 16, 2016
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
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.
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.
Friday, June 10, 2016
A lot of Arduino toys keep arriving in the Asia to USA transit pipeline. Because of the 20 to 25 shipping time I have been trained to put stuffs that I anticipate I can use way ahead of time. I also tend to buy 2 if I anticipate the item would be good because I need to keep one copy of the system for continue code development and maintenance. I however buy 1 if the item is unknown or expensive. Most of these stuff cost between $1.50 to $6 so it is not like I am going poor house doing shopping spree.
Thursday, June 9, 2016
The rude awakening that my code exceeded the 2k bytes of RAM in the Atmel ATmega328 uC's quickly put the brake on the progress. I have spent some time in the weekend investigating what are the big RAM consumers and to find way to work around them. Else I have to readjust the list of features that I set.
Friday, June 3, 2016
Tuesday, May 31, 2016
This is a continuation of a previous post a multi-function display for isolde - part 4. I have been searching for ways to mount the OLED display and the joystick onto Isolde's accessory track. My plan is to hide away the Arduino Uno and the miscellaneous electronics in an enclosure.
Friday, May 27, 2016
The reason I purchased these engine oil pressure and temperature gauge was to get the corresponding sensors. The gauges were so cheap ordered directly from China so I thought the purchase would be a good hedge against my homemade multi-function display project should I decided against it. I would have the option to install these two low cost, yet relatively unobtrusive gauges.
Monday, May 23, 2016
This is the following on post to "a multi-function display for isolde - part 2". I am making some small progress on the programming, and more parts arrived. Among them is the 128x64 pixel OLED display that I was looking forward to play with.
Recently I took Isolde out during an early hot day. The ambient temperature was about 88F which is unseasonably hot for May. In my return trip home, the red LED in the coolant gauge began to blink. I thought to myself this is not good. I was crossing a long bridge at the time and I had yet to gather my faculty as what the LED indicator is for. I initially thought it is the engine oil warning light.
Thursday, May 19, 2016
the previous one in this series.
Tuesday, May 17, 2016
This is the following on post to "a multi-function display for isolde - part 1". I have been giving some thoughts to how to package the bits and pieces of this multi-function display system. It is quite easy to design the electronics and develop the software. What often overlook aspect in project like this is how to package the electronics and dealing with the interconnects. Fabricating good looking enclosures are always the biggest challenge for hobbyists and I am no different.
Monday, May 16, 2016
The idea of a multi-function display for Isolde came to me quite accidentally. It started from when I decided to play with the Arduino microcontroller board. In anticipating its arrival via long shipping time from China I tried to prepare for what simple programs to write. I found this LCD display that I have at home since circa 1994 without any expectation it is of any good or I can find datasheet for it.