It was one of those days that you should learn some chemistry, philosophy and literature. So I thought something like what am I going to do today I started a project I did want to make for a longer time, but for what I never could find the time and concentration. I wanted to make a relay control board. That`s something like when you push on a
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button, an electronic switch switches on (or off, if it was on) and when you push again, it switches back. I`ll refer to this option as the switch option. It is useful when building a remote control for the lamps in your room or something like that. There`s another version of the relay control board, in which the following happens when pushing a button: the relay switches on for a second or so and then switches back. I`ll call this option the toggle option. It`s useful when building a remote control for your computer or so. Now I`d like to have a control board with both possibilities. Therefore, I had to make something like a Mode Function, where the user could say which relay had to switch and which one had to toggle. Also, these options should be saved, also when the power would be low, or the board was disconnected from power. With these requirements I started to build. I used a PIC16F84A, a 20MHz PIC with 64 bytes data EEPROM, which I would use to save the settings of each relay. I used the ports RB0 to RB3 as inputs. The ports RB4-RB7 were outputs, the relays were connected to those pins. If there was an input on RB0, RB7 would switch or toggle, if there was an input on RB1, RB6 would switch or toggle and so on. I used RA4 as an input for a Mode Button, with what I could go to a settings menu. In the settings menu, LED`s on RA0 to RA3 would indicate which setting the relay had (if the LED was on, the relay would...
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