gres
Full Member level 4
This version allows to add 5 buttons keyboard. You can regulate display brightness, sensitivity of the system, and and change effects. Besides, analyzer save settings in eeprom memory, you can choose frequency of converter by jumper. Program also can regulate brightness of VFD display.
Brightness regulation is based on PWM at output OC2 and NPN transistor. By a jumper we can choose VFD display –in this case program want steer PWM channel ( not each VFD can work with). Board is similar to old version. To fit old version you need to solder one transistor and one resistor, and wires to keyboard. And ofcourse install new software. Programs are available for 16*2, 20*2, 24*2 and 20*4. besides there are two versions of the board, of displays with plug at the top 16*1 pin and for displays with slot at the side 2*8pin. Refresh frequency depends on display, how fast driver can open and display data. Fastest displays are VFD. In this case I used that **broken link removed** display, unfortunately it is not full compatible with HD44780 as you can see at the movie – some problems with effects.
More information at http://www.elektroda.pl/rtvforum/topic1570265.html
You can find instruction. Ofcourse not AVR are the same. In this case converter is overclock with high range. Some converters wan’t display top range at all. To prevent that you can set prescaler from 2 to 4. I found that processors before 2009 works much better than younger ones. So if you have some tool with Atmega8, it is worth to chance processor.
At “home” web side you can find also eagle files, board and diagram in pdf for 2*8 and 16*1 display, BIN and HEX inputs and display sources.