Search Results for: atmega8

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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Interfacing MPXV5100 pressure sensor to Atmega8

The MPX5100 series piezoresistive transducer is a state-of-the-art monolithic silicon pressure sensor designed for a wide range of applications, but particularly it is convenient to interface to microcontroller or microprocessor with A/D inputs. This is thin-film metallization, and bipolar processing to provide an accurate, high level analog output signal that is proportional to the applied pressure. More details can be found here MPXV5100 This sensor measures differential pressure comparing to atmospheric so when there is no pressure applied it shows 0kPa;

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Control AVR 8 bit Timer-Counter0 using AVR-GCC

Timers are very important part of embedded systems. They make your life much easier if used properly. Timers runs independently to main program flow, so they can do job independently without disturbing precious calculations done by CPU. You just set up the timer and let it run while your main program perform other tasks. Timers are really easy to set up. In this post an example is made for Atmega8 timers. Other AVR microcontroller models and even different brand chips have similar timers. Atmega8 has two 8 bit timers/counters and one 16-bit timer counter with many abilities. Standard 8-bit Timer/Counter0 features are: Single channel counter; Frequency generator; External Event counter; 10 – bit clock prescaler. TCNT0 is 8 bit timer counter register which keeps the current count number. Timer counter can be clocked by an external clock through pin T0 or from internal via pre-scaller. Timer counter is incrementing (MAX…

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Cheap Arduino compatible boards are same as original

Probably you have noticed that Arduino is spread worldwide. It would be ridiculous to see one manufacturer producing them. The Arduino group produces original board that are named Arduino. This is their trademark. But being open source product, Arduino become popular popular in almost all workshops and so demand is huge. Since building plans are open other electronics manufacturers started building Arduino compatible boards. These are same Arduino boards, but with Arduino name and logo removed. Other than that is 100% compatible to standard Arduino that works with software tools, extensions and modules. Arduino compatible Uno R3 Rev3 development board is one of most known boards. Because this form factor is the first Arduino step in to community.

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Building STK500 AVR ISP programmer with USB

Programmer is one of the first things to think of when starting to deal with microcontrollers. Luckily it is not hard to build fully working programmer almost for any microcontroller as there are tons of open source projects around. So I decided to build stk500 compatible programmer which is actually taken from tuxgraphics.com. I decided not to search for same parts as in original schematics but use what’s on desk. As result I got mix of through hole and SMD soldered board that works great. Short info about STK500 V2 programmer This programmer is a clone of original AVR STK500 programmer. It works on all main platforms including Windows, Linux, BSD and MacOS X. This is mainly because as USB to serial converter there is a FT232RL chip used with full driver support. Probably main reason to build it is that programmer works in AVRstudio where microcontrollers can be programmed…

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AVR DDS3 boards have arrived

Finally some update on AVR DDS3 signal generator. Circuit is practically done and PCBs are made. I decided to go with two microcontrollers on board to make it more functional. One microcontroller Atmega328P is gonna be dedicated to user interface and signal generator control. Second Atmega88 is gonna be used for signal generator only. This will give un-interruptable signal output while changing parameters or simply doing signal sweeps. Simple keypad should be convenient for entering frequency values and menu navigation.

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