Ahh. Holidays. What better time to fiddle with projects?
Not a lot to report on the project front today. More of a quick update on my analog meters, planned projects and new toys.
Purty no? On the upside, I learnt GIMP doesn’t like doing colour inversions, but paint does… Riddle me that internet, riddle me that…
That’s the only update I have for you on that project. I have kinda lost some inspiration on the SD card logging when I couldn’t get some example codes working. Just needs more time than I have had recently.
Moving right along!
What are several things a electronics hobbyist needs?
- Soldering Iron
- Bench Power Supply
Yes? We are in agreement? Ok, maybe not the oscilloscope quite that much, but still. Would be pretty handy…
So I have a solderin iron. It’s old and the tip is burnt through, but it works pretty well. Multimeter? Check. A cheapo $20 one picked up from leading edge electronics when I was 12 I think… Once again. It works to everything I need it to, so far. Oscilloscope? I wish… I’m saving for one at the moment. A cathode ray would be awesome, but I just don’t have the space. So lately I have been thinking of and looking at the digital scopes. As of yet, I don’t know. Peoples thoughts?
Now. Bench power supply. That, I am missing. At the moment I just use the 5V line from my arduino. That’s not really the best way to do things due to the current limitation from that line. We don’t want to be burning out my arduino board now do we? That would just be inconvenient.
So. what to do? A variable bench supply is too expensive. I could mod an ATX powersupply to feed me the 5V and 12V lines from the molex plugs, but the only spare ATX supply I have is dying and they draw a bit of power even with no load attached.
What to do?
Enter brilliant idea.
Build a simple 5V and 3.3V power supply.
Using an LM7805 and a LM317 voltage regulators, feed 12V from an old wall power pack I found lying around into the regulators. Take the output from the LM7805 for 5V, output of LM317 as 3.3V, output direct from the wall pack as 12V. Throw some regulating capacitors and backwards current protector diodes in. Throw a heatsink on the regulators just in case. Simple! I can even build a little adapter to plug in a 9V battery instead of the wall pack. Some pretty LEDs in and switches to turn each segment of the supply on or off. Best idea ever. Best thing is, I have most of the components! Just not the important ones. Like the LM317 and the capacitors… Looks like I’m going back to Jaycar.
After a bit more research I will be ready to draw up a proper cicuit diagram.
Onto my new toy.
Thanks to a post at Hack A Day, I managed to pick up a Texas Instruments experimenter board for half price. Only $13.66! That included shipping! An offer I could not refuse.
The board was a MSP-EXP430FR5739. This board was developed to show off a new(ish) system of memory called FRAM (Ferroelectric Random Access Memory). FRAM boasts a write endurance of 100,000,000,000,000 cycles. What the hell? Thats a huge number. Over 100 billion times more than FLASH memory. That thumb drive with all you back-ups isn’t looking all that safe anymore now is it?
FRAM also writes a hell of a lot faster than FLASH. like, 100 times faster.
You must be thinking, “If FRAM is so good, why do we still use FLASH memory?”
I’m glad you asked that.
While FRAM is more reliable, faster and uses less power, it also have several flaws.
As with all new stuff, It’s expensive! That is the main point in it not taking over FLASH. No one likes spending lots of money, especially big corporations who cut corners to save 1c per product…
Capacity. It just doesn’t, at the moment, have the same capacity for storage compared to FLASH.
That’s enough of me plugging the FRAM. On to plugging the experimenters board infront of me.
This little baby is a 16 bit RISC architecture MCU running at 8MHz. On the board there is a 3 axis accelerometer, a thermistor, 8 LEDs and 2 switches. Other TI boards can be connected to it via a couple of header plugs at the back of the board. All PC and USART conections go through a micro-usb plug at the top of the board. Power is also drawn from USB.
3 axis accelerometer and a PC interface? I think a gesture control for my PC is on the cards…
Well enough from me today. This short post turned into quite a long one. I should probably go do the washing up now… Have fun!