Life-giving to Atmega8

I have got two atmegas from my friend. He stated that they are burned and can be thrown to garbage. He also mentioned that they stopped responding after they were programmed. So I asked him to give those to me to try them. I had in my mind, that this is a result of bad usage of security bits. There is always confusion in these bits, because security bits are programmed by writing ‘0’ values and unprogramed with ‘1’. I didn’t really expected to make them working again as my friend did quite rude experiments with them. What can I say – he was right by saying they are burned. Bu I guess some of you will like to see what I was doing in order to recover them. I decided that he unprogrammed all four security bits ( CKSEL0, CKSEL1, CKSEL2, CKSEL3 )by writing ‘1’ to them. This situation …

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SkinSeg – segmentation of melanoma

SkinSeg is simple tool used for skin lesion segmentation. This little program was developed by Intelligent Systems laboratory students: L. Xu, M. Jackowski, A. Goshtasby, C. Yu, D. Roseman, S. Bines, A. Dhawan, A. Huntley. Their method is working similar as in my earlier experiment with matlab pigmented lesion boundary tracing algorithm. First image is converted to intensity image and then the lesion edges are detected. ant test results: More informative description you can find here Program can be downloaded from here:  This version of the Skin Cancer Segmentation program (skinseg) runs on the Windows 95/NT platforms. Make sure all files reside in the same directory after extraction. No setup program is required to install skinseg on your machine. To run, execute the program skinseg.exe.

Filter output dependency on tolerance of elements

Sometimes we need to project simple filter with particular characteristics. We usually take calculations with ideal parameters and don’t look on tolerances of them. Let us see how simple filter output depends on its elements tolerances. For this let’s choose simple filter circuit: We are going to calculate filter response characteristics. The band pass frequency is taken on 0.707 level of response. We will see how this frequency depends on electronic elements tolerances. I will model elements with tolerances ±10%.

DullRazor – digital skin hair shaver

DullRasor uses image processing techniques to analyze and segments skin areas with dark hair. This program removes dark hairs form images, and makes skin lesion images clean to further processing.    Many skin images contain various numbers of hairs. Other skin segmentation programs may mislead because of hairs – especially dark ones. One solution can be shaving skin before taking pictures of it. But shaving of skin adds more time to processing and this is uncomfortable and in some cases unaesthetic.  Hence, a software approach for dark thick hair removal from skin images is needed.

Skin Cancer causing factors

Substance Where this can be found How to avoid Arsenic Pesticides, wood preservatives, alloy additive non ferrous metals. Use protective clothing when working with arsenic substances Creosote Wood preservative Use protective clothing when working with  creosote substances Ionizing radiation Ionizing radiation are certain industrial sterilization sources Limit exposure if possible. Wear a dosimeter while working with radiation. Sunlight Summer, and when on sun holiday. Avoid strong sunlight, especially at midday. Wear protective clothing to protect your skin. Cover exposed skin with sunscreen of factor 15 or higher. Tar Coal tar Use protective clothing Gluteraldehyde Gluteraldehyde is used as a disinfectant. It is also can be found in X-ray films. Use protective clothing when dealing with gluteraldehyde. Work only in well ventilated areas. Soot Black particles of carbon, produced by incomplete combustion of coal, oil, wood, or other fuels Use protective clothing Pitch It is made by the destructive distillation of …

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Z axis accelerometer MMA1220D from Freescale

MMA1220D is Z axis MEMS accelerometer -8g – +8g. This sensor has capacitive sensor. The output signal is passed through 4 pole low pass filter. It also has internal self test capability. The main features: Integral signal conditioning; Linear output; Ratio metric performance; 4th order Bessel Filter to preserve pulse shape integrity; Calibrated self test; Detection of low voltage also clock monitor and EPROM Parity check status; Can survive high shocks. Where it can be used? It can be perfect tool for Vibration monitoring, control, bearing monitor, PC HDD protection, mouse and joystick, virtual reality, sport diagnostics. The datasheet can be found here: I decided to run sample test of this sensor. For this I just made simple board where I soldered this sensor with SOIC16 package. According to datasheet I put RC filter on sensor output to minimize clock noise. There is schematic: And traced PCB: I used …

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PCB Etcher

After UV-80 vas built there was a thought about automatic PCB Etcher with autonomous Heater and bubble machine. This project is hanging in prefinished phase but it does a job. It was used to etch several PCB’s. As this etcher supposed to be used for making PCB’s using photoresitive technology, the controller supposed to control both = the heater of etching tank and heater of developer. As Sensors there are used AD7416 digital temperature sensors. I decided to publish this small project as this is not clear when it will be finished. When it will be, I will update this article. There is a little dirty drawing with dimensions: The dimensions are as follows 215x275x30 exterior. Inner volume is smaller as glass is 4mm thick. So overall volume is less than 1,2 liter. It is ideal volume to use one bag of ammonium persulphate or 250 grams of FeCl3. The …

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