Frequency counter on АТ90S2313

A virtual frequency meter is a "set" of a PC program and a simple measuring device that is connected to the computer's COM port.The virtual instrument allows you to measure frequency, period, time intervals and count pulses.

Details:http://home.skif.net/~yukol/FMrus.htm

I recommend to assemble a simple design that does not require configuration and most importantly it works! microcontroller programmedPonyProg programmer - excellent programmer, simple, large range of programmable microcontrollers,works under Windows, the interface is Russian.

Magazine "Radio" N1 2002 For Ni-Cd batteries. Allows you to charge 4 batteries.

Frequency meter on Pic 16F84A

Specifications of the frequency meter:

Maximum measurable frequency......................30 MHz;

The maximum resolution of the measured frequency ... .10 Hz.

Input Sensitivity ..................250 mV;

Supply voltage .......................... 8... 12 V:

Current consumption .............................35 mA

Details, firmware:http://cadcamlab.ru

Soldering station on Atmega 8

Switching the soldering iron and hair dryer is carried out by PC switches. The hair dryer is controlled by a thyristor, because. hair dryer at 110v instead of R1 diode cathode to v.6.

Details, firmware: http://radiokot.ru/forum

Digital capacitance meter without desoldering from the circuit

The description is given in the magazine "Radio" No. 6 of 2009. The design was assembled on AT90S2313, Tiny2313 was used without changes in the firmware. In Ponka, I set the checkboxes for SUT1, CKSEL1, CKSEL0, the rest are empty. I didn’t install MAX631, it’s something expensive with us, I decided to power it from the power supply through the stabilizer 7805, R29, R32, R33 put it on the power plus. In addition to the capacitance meter, a probe is mounted in the case to test transistors without desoldering and a low-frequency high-frequency signal generator.

Semiconductor Meter on ATmega8

The device can:

Determine the conclusions of semiconductors;
- determine the type and structure;
- measure static parameters.
Measures diodes, bipolar transistors, JFET and MOS field effect transistors, resistors, capacitors.

The meter is made in the same housing as the FCL meter, the indicator switches between devices with a PC switch.

Frequency meter, capacitance and inductance meter - FCL-meter

The device described below makes it possible to measure the frequencies of electrical oscillations in a wide range, as well as the capacitance and inductance of electronic components with high accuracy. The design has minimal dimensions, weight and power consumption.

Specifications:

Supply voltage, V: 6…15

Current consumption, mA: 14…17

Measurement limits:

F1, MHz 0.01…65**

F2, MHz 10…950

С 0.01 pF…0.5 µF

L 0.001 µH…5 H

External head scheme

More: http://ru3ga.qrz.ru/PRIB/fcl.shtml

Miniature voltmeter on the ATmega8L microcontroller

Here we consider the design of a voltmeter on only one ATmega8L microcontroller and an indicator from an electronic medical thermometer. The range of measured DC voltages is ±50 V. As an additional function, a sound probe mode is implemented to check the integrity of wires, incandescent lamps. The device automatically switches to standby mode when there are no measurements. The microcontroller is powered by two miniature alkaline cells (wristwatch batteries), I put 1 cell at 3v. There will be no need to frequently change the batteries: the current consumption in active mode is only 330 μA, in standby mode - less than 300 nA. Due to its miniature design and capabilities, the device is useful and practical. My board did not fit into the case from the thermometer, and I made it in the case from the felt-tip pen. I made my own board, I installed resistors R5-R7 vertically on the tires. VADZZ helped to make the firmware from the source thanks to him. The indicator pins are from left to right, the pins are at the bottom and facing you.

Scheme (for a full-size scheme, save the image to your computer).

See more details: http://www.rlocman.ru/shem/schematics.html?di=63917

Memory with capacitance measurement function

I wanted to measure the capacity of batteries, imported meters are quite expensive, I found interesting scheme and collected. It works fine, charges, measures, but with what accuracy I find it difficult to say - there is no standard. I measured batteries of fairly decent companies 2700 ma / h - measured 2000. Batteries from toys 700 ma / h -350, ordered Chinese batteries BTY 2500 ma / h - 450 ma / h on EBAY, but decent enough, they work well in toys, much cheaper than batteries.

The device is designed to charge NiMH batteries and control their capacity. Switching between charge / discharge modes is carried out by the SA1 button. The operating mode is displayed using LEDs and decimal points of the first two digits of the seven-segment display.
Immediately after turning on the power, the device enters the charge mode. The indicator shows the charging time. After the programmed time has elapsed, charging stops. The lit point of the fourth category testifies to the end of the charge (and the same discharge). The charge current is defined as C / 10 where C is the battery capacity, set by the trimmer R14.
The principle of operation of the meter is based on calculating the time during which the battery voltage drops to 1.1 V. The discharge current should be equal to 450 mA, R16 is set. In order to measure the capacity, you need to insert the battery into the discharge compartment and start the process by pressing the button! The device is capable of discharging only one battery.

More:http://cxem.net

Universal radio amateur oven

The stove for soldering SMD parts has 4 programmable modes.

Diagram of the control unit (for a full-length diagram, save the image to your computer).

Power supply and heater control

I assembled this design to control the IR soldering station. Maybe someday I'll run a stove. There was a problem with starting the generator, I put 22 pf capacitors from terminals 7, 8 to ground, and it started to start normally. All modes normally work out, loaded 250 watts with a ceramic heater.

More: http://radiokot.ru/lab/hardwork/11/

While there is no stove, I made such a lower heating, for small boards:

Heater 250 W, diameter 12 cm, sent from England, bought on EBAY.

Digital soldering station on PIC16F88x/PIC16F87x(a)

Soldering station with two simultaneously operating soldering iron and hair dryer. You can use different MK (PIC16F886/PIC16F887, PIC16F876/PIC16F877, PIC16F876a/PIC16F877a). Used display from Nokia 1100 (1110). The speed of the hair dryer turbine is electronically regulated, the reed switch built into the hair dryer is also involved. In the author's version applied impulse block power supply, I used a transformer PSU. I all like this station, but with my soldering iron: 60w, 24v, with ceramic heater, big overrun and temperature fluctuation. At the same time, soldering irons of lower power, with a nichrome heater, have smaller fluctuations. At the same time, my soldering iron, with the soldering station from Mikhi-Pskov described above, with firmware from Volu, maintains the temperature to the nearest degree. So a good heating and temperature maintenance algorithm is needed. As an experiment, I made a PWM controller on a timer, applied the control voltage from the output of the thermocouple amplifier, turned off, turned on from the microcontroller, the temperature fluctuation immediately decreased to several degrees, this confirms that the correct control algorithm is needed. External PWM is, of course, pornography in the presence of a microcontroller, but good firmware has not yet been written. I ordered another soldering iron if there is no good stabilization with it, I will continue my experiments with external PWM control, or maybe a good firmware will appear. The station was assembled on 4 boards, interconnected at the connectors.

The diagram of the digital part of the device is shown in the figure, for clarity, two MKs are shown: IC1 - PIC16F887, IC1 (*) - PIC16F876. Other MKs are connected in the same way, to the corresponding ports.

To change the contrast, you need to find 67 bytes, its value is "0x80", for a start you can put "0x90". Values must be between "0x80" and "0x9F".

Regarding the 1110i display (the text is mirrored), if not China, but the original, open the EEPROM, look for 75 bytes, change it from A0 to A1.

Schemes on the microcontroller, articles and descriptions with firmware and photos for the car.

A simple tachometer on the ATmega8 microcontroller

A tachometer is used in cars to measure the speed of any parts that can rotate. There are many options for such devices, I will offer an option on the ATmega8 AVR microcontroller. For my version, you also…

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Color music on the Attiny45 microcontroller in the car

This color music, having a small size and 12V power supply, as an option can be used in a car for any events. The original source of this scheme Radio No. 5, 2013 A. LAPTEV, Zyryanovsk, Kazakhstan. Scheme…

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Heated mirror and rear window controller

Allows you to control one button separately heated rear window and mirrors, plus a customizable off timer up to one and a half hours for each channel. The circuit is built on the ATtiny13A microcontroller. Work description:

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Car light dimmer

Almost all cars have interior light control, which is carried out using an on-board computer or a separate on-board system. The light turns on smoothly, and also goes out with a certain delay (for ...

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GSM alarm system with mobile notification

I present a very popular car alarm circuit based on the ATmega8 microcontroller. Such an alarm gives an alert to the administrator's mobile phone in the form of calls or SMS. The device integrates with a mobile phone using ...

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Blinking stopak on the microcontroller

Did new version blinking stack. The operation algorithm and control scheme are different, the size and connection are the same. It is possible to adjust the blinking frequency, the duration before the transition to a constant glow and the duty cycle ...

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DRL plus strobe lights

This craft allows you to strobe with LED DRLs. The craft has a small size, only one button control, wide customization options. The size of the board is 30 by 19 millimeters. On the back side there is a...

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We make and connect the door closer to the alarm

The number of cars with automatic windows is constantly growing, and even if the car does not have one, many do it themselves. My goal was to assemble such a device and connect it to ...

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LEDs turn on at speed

It turned out to be a “by-product”: it was necessary to test the mode of operation of the speed sensor for the project of displaying gears on a 5x7 matrix, for this I assembled a small circuit. The circuit can turn on the LEDs depending on ...

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Digital tachometer on AVR microcontroller (ATtiny2313)

The tachometer measures the speed of rotation of parts, mechanisms and other units of the car. The tachometer consists of 2 main parts - a sensor that measures the speed of rotation and a display where it will be ...

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Simple digital speedometer on ATmega8 microcontroller

The speedometer is a measuring device for determining the speed of a car. According to the measurement method, there are several types of speedometers: centrifugal, chronometric, vibration, induction, electromagnetic, electronic and, finally, GPS speedometers.

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Smooth ignition tidy on the microcontroller

This version is slightly different in circuitry: a second setting button has been added and the ignition speed potentiometer has been removed. Features: Two separate independent channels. There are three groups of adjustable parameters for each channel: delay time before start…

Hello Datagorians!

After the publication of my first article, I was inundated with questions about microcontrollers, how, what, where, why ...

So that you can figure out how this black box works, I will tell you about the microcontroller (hereinafter MK) ATmega8. In principle, Atmel produces a whole series of MKs of the AVR family - these are the Tiny and Mega subfamilies. I will not paint the merits of certain MKs, it's up to you to decide what suits you best. Some members of the extended family:

So, ATmega8, the simplest MK of all ATmegas:

Let's start studying the insides according to a simplified structural diagram:

This is a generalized scheme of all ATmega.

All AVR microcontrollers are built according to the so-called Harvard architecture, that is, separate addressing of program memory and data memory is used. The advantages of this architecture are increased speed, for example, ATmega executes one instruction per clock pulse, that is, at a frequency of 16 MHz, the microcontroller performs 16 million operations per second.

And now about the tripe in order.
1. The clock generator synchronizes all internal devices.
2. ROM is a read-only memory device used to store the program and immutable data (constants).
3. Command decoder - he is the most important here, he controls everything that comes to his hand.
4. ALU - arithmetic logic unit, performs arithmetic (addition, subtraction, etc.) and logical (AND, OR, NOT, XOR) operations on numbers.
5. RON - general-purpose registers, the ALU operates with them, and are also used for temporary data storage. RON registers can be combined into register pairs:
r26: r27 - X;
r28: r29 – Y;
r30: r31-Z.
Register pairs are used to indirectly address data in RAM.
6. RAM - Random Access Memory, used to store data, arrays and stacks.
7. PORTA-PORTn - communication with the outside world, input / output ports, well, it’s clear why ...
8. Spec. UVV - special input / output devices, controllers of various peripherals, for example USART (another COM port), sometimes USB, ADC, DAC, I2C, in short, what is not there ...

Well, yes, this is all theory, but you can’t wait to glue something, try it, and make it work! Then we list what we need:

1. A programmer with the appropriate software, I wrote about this in a previous article;
2. The C compiler, Code Vision AVR, has a good toolkit for developing programs for MK;

Before you start programming in C, it would be nice to get acquainted with some literature on this language, for example, there is a wonderful book by Kernighan and Ritchie "The C Language".

Okay, let's start...

Test scheme.

Let's make a diagram like this:

This will be the base model. By the way, it is better to assemble the circuit on a breadboard, and put the MK into the socket. But such a scheme is meaningless. Add, for example, an LED, and do not forget about the current-limiting resistor. Connect it to the zero output of port B.
The schema will look like this:

Turn on the power… ZERO!!! What would you like without the program?
Means…

We are writing a program!

So you've got CVAVR up and running, what's the first thing to do? We start the Code Wizard AVR wizard by clicking on the button with the gear in the toolbar, the wizard window will appear:

Here we select the type of MK and the clock frequency. Next, go to the Ports tab:

And we configure which bit of which port we will be configured for input or output, port B bit 0 will give us a signal, and receive the rest.
To save the settings, select the File / Generate Save and Exit menu, enter the file names for all subsequent requests, it is desirable that they be the same, for example, “prj”. That's it, we have generated the source code of the program with the settings specified in the wizard.

Let's see what we got. The first 22 lines are a comment, that is, it has no effect on the actions of the program, so everything between "/*" and "*/" is a comment, and the compiler ignores the whole thing. In the 24th period, we have a header file connected, it describes how which registers are called and at what address they are located. For C programming, the details are redundant here.
From line 28, we begin the main program with a function definition main(),

Let's scroll down. Pay attention to lines 36 and 37, here a value is assigned to port B and the direction of transmission is selected. Basically, it looks like this:

That is, if one is written to any bit of the DDRB register, then the corresponding bit of port B will work on the output. In our case, this is bit 0.
By the way, the ports in ATmega have one nice feature, even if the port is set to input, and write ones to the PORTx register, then the internal pull-up resistors will be connected to the power plus, which eliminates the use of external resistors. This is convenient when connecting any sensors and buttons.

Let's compile the program, to do this, press the Make the Project button, or through the Project / Make menu. There shouldn't be any errors unless you've corrected something.

Let's open the C:\cvavr\bin\ folder, find the prj.hex file there. This is the program compiled by us for MK. Let's connect the programmer to the PC and MK. Let's start the Pony Prog program and drag the prj.hex file into its window. Turn on the power of the MK and fill it with our program ... Again, nothing? And the problem is that we didn’t output anything to the zero bit of port B, or rather, we output it, only it’s zero. And in order for our LED to light up, we need to output a unit. So let's do it, replace in line 36 "PORTB=0x00;" to "PORTB=0x01;". Let's compile the program again. And in the Pony Prog program, reload the file using the Ctrl + L keyboard shortcut or the File / Reload Files menu. Let's erase the MK and again fill the "firmware" into it. HOORAY!!! IT WORKS!!!

By the way, Pony Prog supports scripts, and in order not to suffer with rebooting, erasing and writing, you can simply write a script with the .e2s extension, and call it, for example, prog.e2s. You can do this with notepad. Its content will be like this:

SELECTDEVICE ATMEGA8
CLEARBUFFER
LOAD-ALL prj.hex
ERASE-ALL
WRITE-ALL

Place the script in the same folder as the .hex file and run it with a double click. You can put a shortcut on the desktop, it's as convenient for anyone ...

To be continued…

Atmega8 microcontrollers are the most popular representatives of their family. In many ways, they owe this, on the one hand, to the simplicity of work and a clear structure, on the other hand, to a fairly wide functionality. The article will cover Atmega8 programming for beginners.

general information

Microcontrollers are found everywhere. They can be found in refrigerators, washing machines, telephones, factory machines, and a wide variety of other technical devices. Microcontrollers range from simple to extremely complex. The latter offer significantly more features and functionality. But to understand immediately in complex technology will not work. Initially, you need to master something simple. And the Atmega8 will be taken as a sample. Programming on it is not difficult due to the competent architecture and friendly interface. In addition, it is the owner of sufficient performance to be used in most. Moreover, they are used even in industry. In the case of Atmega8, programming requires knowledge of languages such as AVR (C/Assembler). Where to start? The development of this technology is possible in three ways. And everyone chooses for himself where to start working with Atmega8:

Programming via Arduino.
Buying a finished device.
Self-assembly of the microcontroller.

We will consider the first and third points.

Arduino

This is a convenient platform, designed in the form that is suitable for quickly creating various devices. The board already has everything you need in the form of the microcontroller itself, its strapping and programmer. Following this path, a person will receive the following benefits:

Low requirement threshold. You do not need to have special skills and abilities to develop technical devices.
A wide range of elements will be available for connection without additional preparation.
Rapid start of development. With Arduino, you can go straight to creating devices.
The presence of a large number teaching materials and examples of implementations of various designs.

But there are also certain disadvantages. So, Arduino programming Atmega8 does not allow you to plunge deeper into the world of the microcontroller and understand many useful aspects. In addition, you will have to learn a programming language, which is different from those used by AVR (C / Assembler). And one more thing: Arduino has a rather narrow line of models. Therefore, sooner or later there will be a need to use a microcontroller, which is not used in the boards. But in general, this is a good option for working with Atmega8. Programming with Arduino will get you started in the world of electronics. And a person is unlikely to give up because of failures and problems.

Self assembly

Thanks to the friendliness of the design, they can be made by yourself. After all, this requires cheap, affordable and simple components. This will allow you to get a good understanding of the Atmega8 microcontroller, which will seem easier to program after assembly. Also, if necessary, you can independently choose other components for a specific task. True, there is a certain minus here - complexity. It is not easy to assemble a microcontroller on your own when you do not have the necessary knowledge and skills. We will consider this option.

What is needed for assembly?

Initially, you need to get the Atmega8 itself. Programming a microcontroller without it, you know, is impossible. It will cost several hundred rubles - while providing decent functionality. There is also the question of how Atmega8 programming will be done. USBAsp is a pretty good device that has proven itself from the best side. But you can use some other programmer. Or assemble it yourself. But in this case, there is a risk that, with poor-quality creation, it will turn the microcontroller into a non-working piece of plastic and iron. Also, the presence of a breadboard and jumpers will not hurt. They are not required, but will save your nerves and time. And finally - you need a 5V power supply.

Atmega8 programming for beginners by example

Let's look at how, in general terms, the creation of a device is carried out. So, let's say that we have a microcontroller, an LED, a resistor, a programmer, connecting wires, and a power supply. The first step is writing the firmware. It is understood as a set of commands for the microcontroller, which is presented as a final file having a special format. It is necessary to register the connection of all elements, as well as interaction with them. After that, you can start assembling the circuit. Power must be applied to the VCC pin. To any other, designed to work with devices and elements, a resistor is connected first, and then an LED. In this case, the power of the first depends on the nutritional needs of the second. You can navigate by this formula: R=(Up-Ups)/Is. Here p is the power and s is the LED. Let's imagine that we have an LED that consumes 2V and requires a supply current of 10 mA, we translate it into a more convenient form for mathematical operations and get 0.01A. Then the formula will look like this: R \u003d (5V-2V) / 0.01A \u003d 3V / 0.01A \u003d 300 Ohms. But in practice it is often impossible to find the ideal element. Therefore, the most suitable is taken. But you need to use a resistor with a resistance higher than the value obtained mathematically. Thanks to this approach, we will extend its service life.

And what's next?

So, we have a small scheme. Now it remains to connect the programmer to the microcontroller and write the firmware that was created into its memory. There is one point here! When building a circuit, it is necessary to create it in such a way that the microcontroller can be flashed without soldering. This will save time, nerves and extend the life of the elements. Including Atmega8. In-circuit programming, it should be noted, requires knowledge and skills. But it also allows you to create more advanced designs. After all, it often happens that during desoldering the elements are damaged. After that, the scheme is ready. You can apply voltage.

Important Points

Want to give newbies helpful tips about programming Atmega8. Do not change built-in variables and functions! It is advisable to flash the device with the created program after checking it for the absence of “eternal loops”, which will block any other interference, and using a good transmitter. In the case of using homemade products for these purposes, you should be mentally prepared for the failure of the microcontroller. When you flash the device using the programmer, you should connect the corresponding outputs VCC, GND, SCK, MOSI, RESET, MISO. And don't break safety rules! If technical specifications provided that there should be a power supply of 5V, then you need to adhere to just such a voltage. Even the use of 6V elements can negatively affect the performance of the microcontroller and shorten its service life. Of course, 5V batteries have some differences, but, as a rule, everything is within reasonable limits. For example, the maximum voltage will be kept at 5.3V.

Training and improvement of skills

Luckily, the Atmega8 is a very popular microcontroller. Therefore, it will not be difficult to find like-minded people or just knowledgeable and able people. If there is no desire to reinvent the wheel, but just want to solve a certain problem, then you can search for the required scheme in the vastness of the global network. By the way, a little hint: although robotics is quite popular in the Russian-speaking segment, but if there is no answer, then you should look for it in the English-speaking one - it contains an order of magnitude more information. If there is some doubt about the quality of the recommendations available, then you can look for books that discuss Atmega8. Fortunately, the manufacturing company takes into account the popularity of its developments and provides them with specialized literature, where experienced people tell what and how, and also give examples of the operation of the device.

Is it difficult to start creating something of your own?

It is enough to have 500-2000 rubles and a few free evenings. This time is more than enough to get acquainted with the Atmega8 architecture. After a little practice, you can safely create your own projects that perform certain tasks. For example, a robotic arm. One Atmega8 should be more than enough to convey the basic motor functions of the fingers and hand. Of course, this is a rather difficult task, but quite feasible. In the future, in general, it will be possible to create complex things that will require dozens of microcontrollers. But this is all ahead, before that you need to get a good school of practice on something simple.

Frequency counter on АТ90S2313

Details:http://home.skif.net/~yukol/FMrus.htm

Magazine "Radio" N1 2002 For Ni-Cd batteries. Allows you to charge 4 batteries.

Frequency meter on Pic 16F84A

Specifications of the frequency meter:

Maximum measurable frequency......................30 MHz;

The maximum resolution of the measured frequency ... .10 Hz.

Input Sensitivity ..................250 mV;

Supply voltage .......................... 8... 12 V:

Current consumption .............................35 mA

Details, firmware:http://cadcamlab.ru

Soldering station on Atmega 8

Switching the soldering iron and hair dryer is carried out by PC switches. The hair dryer is controlled by a thyristor, because. hair dryer at 110v instead of R1 diode cathode to v.6.

Details, firmware: http://radiokot.ru/forum

Digital capacitance meter without desoldering from the circuit

Semiconductor Meter on ATmega8

The device can:

The meter is made in the same housing as the FCL meter, the indicator switches between devices with a PC switch.

Frequency meter, capacitance and inductance meter - FCL-meter

Specifications:

Supply voltage, V: 6…15

Current consumption, mA: 14…17

Measurement limits:

F1, MHz 0.01…65**

F2, MHz 10…950

С 0.01 pF…0.5 µF

L 0.001 µH…5 H

External head scheme

More: http://ru3ga.qrz.ru/PRIB/fcl.shtml

Miniature voltmeter on the ATmega8L microcontroller

Scheme (for a full-size scheme, save the image to your computer).

See more details: http://www.rlocman.ru/shem/schematics.html?di=63917

Memory with capacitance measurement function

I wanted to measure the capacity of the batteries, imported meters are quite expensive, I found an interesting circuit and assembled it. It works fine, charges, measures, but with what accuracy I find it difficult to say - there is no standard. I measured batteries of fairly decent companies 2700 ma / h - measured 2000. Batteries from toys 700 ma / h -350, ordered Chinese batteries BTY 2500 ma / h - 450 ma / h on EBAY, but decent enough, they work well in toys, much cheaper than batteries.

More:http://cxem.net

Universal radio amateur oven

The stove for soldering SMD parts has 4 programmable modes.

Diagram of the control unit (for a full-length diagram, save the image to your computer).

Power supply and heater control

More: http://radiokot.ru/lab/hardwork/11/

While there is no stove, I made such a lower heating, for small boards:

Heater 250 W, diameter 12 cm, sent from England, bought on EBAY.

Digital soldering station on PIC16F88x/PIC16F87x(a)

Soldering station with two simultaneously operating soldering iron and hair dryer. You can use different MK (PIC16F886/PIC16F887, PIC16F876/PIC16F877, PIC16F876a/PIC16F877a). Used display from Nokia 1100 (1110). The speed of the hair dryer turbine is electronically regulated, the reed switch built into the hair dryer is also involved. In the author's version, a switching power supply is used, I used a transformer PSU. I all like this station, but with my soldering iron: 60w, 24v, with ceramic heater, big overrun and temperature fluctuation. At the same time, soldering irons of lower power, with a nichrome heater, have smaller fluctuations. At the same time, my soldering iron, with the soldering station from Mikhi-Pskov described above, with firmware from Volu, maintains the temperature to the nearest degree. So a good heating and temperature maintenance algorithm is needed. As an experiment, I made a PWM controller on a timer, applied the control voltage from the output of the thermocouple amplifier, turned off, turned on from the microcontroller, the temperature fluctuation immediately decreased to several degrees, this confirms that the correct control algorithm is needed. External PWM is, of course, pornography in the presence of a microcontroller, but good firmware has not yet been written. I ordered another soldering iron if there is no good stabilization with it, I will continue my experiments with external PWM control, or maybe a good firmware will appear. The station was assembled on 4 boards, interconnected at the connectors.