Audio processor TDA8425 microcontroller controlled by PIC16F876A
We wish you good day! Despite the fact that this site has several schemes TONE, I decided to create their own project in order to meet our common needs.
The aim of this project was to:
- Support for 16x2 LCD display on the controller HD44780
- Controlled by a 3x3 matrix of buttons
- Control remote control that works via RC-5 from Philips
- Separate line input and the input to the receiver, MP3 player or other
- Management power external devices
- Multilingual
- Management enoderom PEC16, PEC12 or similar is pin
- Two modules on a single board
- Countdown to switch to Stand-By
- Auto-save settings when power is turned off
- Support for 16x2 LCD display on the controller HD44780
- Controlled by a 3x3 matrix of buttons
- Control remote control that works via RC-5 from Philips
- Separate line input and the input to the receiver, MP3 player or other
- Management power external devices
- Multilingual
- Management enoderom PEC16, PEC12 or similar is pin
- Two modules on a single board
- Countdown to switch to Stand-By
- Auto-save settings when power is turned off
Huge request. Read this article to the end that there is no stupid questions on the forum.
In the end, we got the tone-assembled at the company Philips TDA8425 audio processor and Microcontroller from Microchip Technology PIC16F876A
These chips look like this
These chips look like this
Despite the fact that the TDA8425 chip was developed in October 1988, it is very popular among radio amateurs around the world for over ten years.
It is a complete audio processor, which is controlled by a digital bus I2C (I-Tu-Sea, SDA - data , SCL - sync), two stereo inputs, which are switched to each other by an external controller. Treble adjustment range is -12 to +12 dB, the bass from -12 to +15 dB (step 3 dB), the volume of -64 to +6, step 2 dB.
TDA8425 chip can operate in four different modes: stereo, pseudo stereo , extended or spatial, and mono. In the "stereo" mode works as a tone-all "normal" stereo chip. In the "pseudo" mode on the left channel included a slight delay, which is distinctly decorated with sound. In the "enhanced stereo" 50% of the signal from one channel is mixed with the other, which gives a small stereo widening sound and lightly decorated. The two above described functions are very useful even in mono playback. In the "mono" signal of both channels is mixed by internal resistors.
It is a complete audio processor, which is controlled by a digital bus I2C (I-Tu-Sea, SDA - data , SCL - sync), two stereo inputs, which are switched to each other by an external controller. Treble adjustment range is -12 to +12 dB, the bass from -12 to +15 dB (step 3 dB), the volume of -64 to +6, step 2 dB.
TDA8425 chip can operate in four different modes: stereo, pseudo stereo , extended or spatial, and mono. In the "stereo" mode works as a tone-all "normal" stereo chip. In the "pseudo" mode on the left channel included a slight delay, which is distinctly decorated with sound. In the "enhanced stereo" 50% of the signal from one channel is mixed with the other, which gives a small stereo widening sound and lightly decorated. The two above described functions are very useful even in mono playback. In the "mono" signal of both channels is mixed by internal resistors.
Let's take a look at the diagram strapping Audio Processor
Diagram types taken from datasheet. The only thing that has been replaced is input and output capacitors.
Let's look at the concept of tying the microcontroller
As can be seen by the scheme in the matrix has 3 buttons that are designated as Res *. It reserved the function key that you can change.
Many newcomers may be surprised by the item, which is designated as Z1 - 8MHz. That, my friends, the quartz resonator for eight megahertz that specifies the frequency of the clock of the microcontroller.
It is possible that part which is designated as PEC12/PEC16, also can confuse beginners. This is a mechanical encoder.
It looks like this
Many newcomers may be surprised by the item, which is designated as Z1 - 8MHz. That, my friends, the quartz resonator for eight megahertz that specifies the frequency of the clock of the microcontroller.
It is possible that part which is designated as PEC12/PEC16, also can confuse beginners. This is a mechanical encoder.
It looks like this
The following figure PCB
I do not know why, but contrary to the template I placed across the output resistors on the audio processor 10 kilohms.
So as you can confuse the fact that the scheme applied SMD resistors that as it may seem difficult to solder.
So as you can confuse the fact that the scheme applied SMD resistors that as it may seem difficult to solder.
Photo taken on a piece of a school notebook. Trust me. Solder these parts are not so difficult and ush. On the channel on YouTube easyelectronics is not a video lesson on how to do it. It was not advertising, and recommendations for beginners.
easily payayu I like this SMD soldering
easily payayu I like this SMD soldering
Soldering iron 25 watt, 220 volt
PCB can be made with a marker or by PROPHET (Laser utyuzhnaya technology)
First soldered SMD components thus: Apply flux on the track, a tray component tweezers, about their labeling will explain below. Next, take a bit of solder on the soldering iron and solder the components.
Marking SMD resistors and ceramic capacitors
marking 474 corresponds to 470000, ie 474 = 47 * 10 ^ 4
10 pokofarad is marking 100. 10 nanofarat ie 10,000 pF is marking 103 ie 10 * 10 ^ 3
is similar to a resistor. 153 = 15,000 ohms or 15 kilo-ohms, ie 15 * 10 ^ 3
After soldering SMD components soldered jumper, then resistors, capacitors, IC sockets, terminals for wire, pin connectors (if desired) and then just wash with acetone flux, soldered quartz resonator.
I got something like this
First soldered SMD components thus: Apply flux on the track, a tray component tweezers, about their labeling will explain below. Next, take a bit of solder on the soldering iron and solder the components.
Marking SMD resistors and ceramic capacitors
marking 474 corresponds to 470000, ie 474 = 47 * 10 ^ 4
10 pokofarad is marking 100. 10 nanofarat ie 10,000 pF is marking 103 ie 10 * 10 ^ 3
is similar to a resistor. 153 = 15,000 ohms or 15 kilo-ohms, ie 15 * 10 ^ 3
After soldering SMD components soldered jumper, then resistors, capacitors, IC sockets, terminals for wire, pin connectors (if desired) and then just wash with acetone flux, soldered quartz resonator.
I got something like this
Configuration and Diagnostics
To program the microcontroller PIC16F876A programmer I used ExtraCheap, schematically below
But just the same, you can use PicKit2, USB-GTP and Extra-PIC, articles presented here RadioKOT. The program WinPic800 3.55G
After programming the microcontroller insert it into the socket, or solder directly to the board. Whatever you like.
Put trimmer R4 in the middle position, connect all cables, power supply provides a regulated 12 volts. Immediately after power-on indicator lights must decrease, and a little less than half a second you'll be able to observe the following picture
After programming the microcontroller insert it into the socket, or solder directly to the board. Whatever you like.
Put trimmer R4 in the middle position, connect all cables, power supply provides a regulated 12 volts. Immediately after power-on indicator lights must decrease, and a little less than half a second you'll be able to observe the following picture
after which the display will clear and the microcontroller waits for user commands. He'll be waiting on command. Turning on his remote control or the buttons and indicator should "light up."
If the light is right after power lights, but did not die down, and the first line of the LCD display is not clear (to be filled in, as it were), it may be the following reasons:
- No power to the controller.
- If the first line of the LCD will be cleared (translucent) may be defective regulator 78L05 or incorrect cable or wire loop.
- Do not "wound up" clock. Try fast short-circuit one of the conclusions of quartz output regulator 78L05. I helped.
- No power to the controller.
- If the first line of the LCD will be cleared (translucent) may be defective regulator 78L05 or incorrect cable or wire loop.
- Do not "wound up" clock. Try fast short-circuit one of the conclusions of quartz output regulator 78L05. I helped.
If all booted after pressing the Stand-By twist the resistor R4 as long as the text on the LCD display is no longer "vary smoothly" at switching points of adjustment. This is particularly evident when looking at the light from above. After you should see a picture
If all goes well, connect the player to the input of the audio processor, the linear output of the computer, or another source. To connect the output of powered speakers or an amplifier. Turn on the music, the columns should hear the music.
In the beginning of the article it was mentioned on power management, external devices. For beginners, this task uhh, if not simple. But asking me to change the firmware on your taste I am happy to help!
Let's talk about multilingual. To change the language of need or remote control, or edit the firmware. But, as mentioned above, you can ask me to do so, something to go to the menu to change the language it was possible using the buttons.
As a re-
As a re-
Well, and as proof that it works, I'll give you a video
It describes the details of additional features as well as a demonstration of the work.
I would like to say a huge thanks to Alexander Hanzhovu, "kotopsu" and "kelevra" for the fact that my project is pre-tested and evaluated it. Below is a screenshot of the two messages from the forum, sent long before the publication of the article.
The following picture of the user "CatDog"
(the slider is different because "CatDog" used one of incompletely modified firmware)
(the slider is different because "CatDog" used one of incompletely modified firmware)
Another photo from Alexander Hanzhova
(was used non-standard firmware)
(was used non-standard firmware)
This project and your modified code can be evaluated in the project Proteus. For the correct display of the Cyrillic alphabet to replace the library file in the folder LCDALPHA.DLL MODELS. It should be noted that the LCD 16x2 in Proteus is not quite working correctly. In real life a little differently.
Repeat. If you want to change the firmware, then write to my e-mail vhemaster@mail.ru and I am happy to help! I used the Hi-Tech C Compiler PRO 9.65.
hello, nice project!
BalasHapusI would like to know, if you can update links for the project files?
Thank you.
Have a nice evening.