2014. február 28., péntek

DIP form factor ARM - This is sick

Here comes the ARM. To be able to use it in breadbord we need a DIP form factor version.Unfortunately this is not tom much exists.To be honest. Only two type exists:
  • NXP LPC810
  • NXP LPC1114 (one derivative)
The first is a DIP-8 chip, so it is not enough for the majority of applications. The second one is much better.
Nowadays it is a usual thing, that the bigger (in our case 28) pin ICs are hit the market in narrow (300mil) package. This is not the case regarding  the LPC1114. This IC is located in a 600mil package.
There are people who didn't like it.
And there are people, who does something against it:


My opinion: It is sick.

MCU Change - ARM

Because nobody answered to my question, I should do it. So the solution comes here.
First of all, who is manufacturing ARM Cortex based MCU's?
The known ones:
  • Texas Instruments
  • Freescale (aka Motorola)
  • ST Microelectronics (SGS-Thomson)
  • NXP (aka Philips)
  • Atmel
  • Toshiba
So the winner is.... no, no, none of above. I've development kits for four of the above six.
So the answer:
Nuvoton
You never heard about it? Sure? And on the name Winbond? You didn't get it either? But you can find components from them in your PC.
And the price?
The type in the example is NUC120LC1BN. And the price is 430Ft+VAT!!! (around $1.50)

2014. február 26., szerda

MCU - The Change

I'm thinking about plenty of new projects and new version of old ones. I feel that the MSP430 not suits anymore.
The aspects lead me to the MSP430 originally are getting irrelevant:
DIP package - I've learned handling, soldering SMD components. I've the knowledge and the source for manufacturing professional PCBs
Unbeatable priced development platform. The TI MSP430 Lanuchpad is still the cheapest one on the market, even it is not $5 anymore. On the other hand the competing manufacturers also speeding up. There is almost no MCU on the market what has no cheap development platform.
The first article what I read on the "Hobbielektronika" portal. It has no relevance now according to the knowledge and experience I've now.
I see if I start anything new (new project) with MSP430 I always facing significant difficulties.
From the hardware side:
Low pin count, missing peripherals. It leads me to use additional components what increase the cost of the project. On the other hand if I use other devices than the value line, the cost of the device and the required development platform will be high.
From software side:
Somebody may smarter than me and found easy solution, but for me the handling of the peripherals (especially the I2C bus) was a nightmare. There is no correct, working driver, and the code in the TI master library was partially usable after a thorough rewriting. I think, I'd like to spend my time to work out my ideas rather than this type of problems.
Because of the reasons above, I'm looking for the solution for a while. I think, I found it.
Pick a project example. Something like the controller of the UV lightbox (but not that). What I need for it?
  • 4 digit 7-Segment LED display (it is 12 GPIO with normal multiplexing)
  • A few button input (let say 4)
  • Buzzer
  • 1 output (to switching the load)
  • 1 input (trigger)
  • Serial communication (over USB)
  • RTC (yes, it will have a clock inside)
  • One, but more likely two timers
  • External 32.768kHz XTAL
  • BSL
A good part of this is not in the MSP430G series. The others (series) are pricy, typically requires state of the art development platforms (the classic Launchpad is not really suits). In addition like it or not, the MSP430 is a proprietary technology. From my point of view I would rather choose an ARM MCU. I did it already.
We can presume that a 32 bit MCU has higher price point than an MSP430 (or even an AVR or PIC).
This is not definitely true. Based on the requirements above I put together a comparison table:


There is two things what I will not tell now. The price and the exact type. You can guess (here in the comments).

2014. február 24., hétfő

Project idea - VU Meter

I'm somehow fiend of the LED bar (or VFD) based VU meters. If it contains more elements it is better. Sometime in my youth (What? I'm still jung!!!) I wanted to build one, I bought a fist of LEDs for it, but it remained a dream. At that time the audio equipments had something like that. For today it is out of stile.
I know exactly that the "thing" has no usage value. But I want one. If I start to build something like that I want an MCU in it and not a bunch of analog circuity.
I think, pick 50pcs LEDs/side and in multiplexed mode connecting to the MCU. I pick the ADC of the MCU and after some rework display the ADC output on the LEDs.
I also need some analog front-end for this.
I guessed that not myself the only fool who want one as a separate equipment or part of something. If I create this, I'll sell it also.
The type of the MCU is not decided yet (or maybe, just I wont tell it to you).
The LEDs are an other question. On the PCB I'd like to have place for three different kind of LEDs:
1. Bargraph. The Kingbright manufactures sutch thing:






This is one option but the price is a high. Based on the color and intensity the prices are around $1-$1.5 for the 10 element bar. The full component cost will be above $15.
2. Separate reactangle shaped LEDs
This can be bought around $0.03 a piece.
3. SMD LEDs
The price is the same, but who want to handsolder them???

The idea is to create a PCB what is able to accommodate the all three types (or at least two).

ARM Course 8. - LAB 8

Yesterday evening I've finished the module 8. With this I'm standing at 47% (I need 70%). I still not feel the high level of this course. It take something like ten minutes to write and test the code, the construction of the circuit on the breadboard.
I've documented the result here:


32 Bit, 80 MHz and the LED blinking (my first PC had a 16 Bit 8 MHz CPU with a little more result). The biggest challenge during the construction was that I caught a bug. To be precise, not a bug but a "misprint".
I was looking for the the PE0 pin on the board. Finally I fond. Here:


Check the yellow marked designators! The two parts of the photo displays a part of the top and the bottom side of the Launchpad.

2014. február 20., csütörtök

Project idea - Lightbox

No, no, it is not my UV Lightbox. It is not alike.
I'm creating lot of things. The photos made about it are disappointing. I should put together a "lightbox" for photography. Something like this:
http://www.csik.net/node/688
Naturally  I don't want a cardboard frame, but wood. It would be good if it is foldaway, to not consume to much space. The lighting is other matter. It can be something homemade LED based one.

Frequency Counter V2 13. - Populated

In the mean time all of the components (except the screws of the box) arrived.
I assembled one in its final format:


The following will come:
  • Finish the programing connector. I used the pinless, shifted hole programing connector on this design. It is not the first time, but the first occasion when I'll really using it
  • It has a power connector, but I was not able to find a plug to it on the first try at home, so I have to buy one and make a cable to it
  • If the whole stuff working then next will be the calibration
  • The software at 95% readiness level. I've to finish it