Hi there I was wanting to start a project (a clock to be specific) and I need to know if there is any thing like this. Basicly I'm looking for some thing that has an input pin and like 7 out put pins and a reset pin. I would like for it to work like this. I would set the input pin high then back low and that would turn on output 1 then I would set he input pin high then low and the Ic would tun on output 2 and so on. I'm not sure if there is any thing like this or not.
The first thing that came into my mind was two ics wired together to do the job. A 74xx90 and a 74xx42. Look at this for counting 74LS90 - Counter O:BCD 74LS42 Data sheet - BCD to DEC decoder They are really easy to wire up together; there may be an IC dedicated to that function but I am not sure.
Thanks for the links. It seems like some one would make a chip that dose what I need. It seems a simple function. The plan was to use small led's to make a binary clock for my car sence the analog one is broke (78 camaro). I'm not sure what I can use as the clock part though.
For a binary clock, you will only need the 74LS90 and not the 74LS42 since the 74LS42 does not output in binary, the 74LS90 does - well BCD, but close enough for what you want. The reason, I think, they do not make a counter to output directly to nine pins:1, 2, 3... is because there are not many applications that require it. If someone wants a mumerical output, say 7-segment, then they just utilize a direct BCD-7 segment display IC- I think 74xx47, or direct it toward a display unit in binary. The decoder chip to the output display is a computer, so it would be easier for it to accept binary. Otherwise they would have to do something such as Counter->BCD->Dec->BCD->Decoder->Output.
you can easily make a rather nifty binary clock. If you've got a PIC lieing about you don't have to worry about ordering some logic gates (i always hate buying a 10cent component and paying 6$ for shipping!)
maby he doesnt know how to program in ASM (like me) Unfortuantly buyig a pic programmer dosnt immediately mean you can "do pics" (beleve me, i bought 2 programmers and it still didnt work!)
sorry but i'm from the school of learn basic principles enough to make judgement of what to buy. The thing is its simpler to write a program to do this, than it is to use counter ICs + clock source.
I know asm so its cool. I was planing on using a small pic to controll the clock + the BCD. I'm unsure of where to get the clock source though.
I'm in the US and the clock is going in my camaro. I thought about doing an analog clock out of leds to but that would take to much room I think.
Just use a crystal on the PIC for the clock source. The LED clock v1 that I have in my sig loses only 1 second every 4 months now.
I could probably off set that even further by using a high precision resonator/crystal. I'm guessing that you made a 1 second delay and then when it exits that it sets one of the output pins high and then low? If so I guess all I need to do is figure out how to display the time in this format HH:MM:SS. I'm not sure how to make it so that when it gets to 59 seconds it adds one to the MM section. Any help on how to lay out the clock would be great. EDIT: I got a crazy idea. I could used rgb leds which using primary and secondary colors I would have 1 (led off) + 6 color combinations. This would be tricky as crap to read but colorfull
you can actually buy RTCs or Real Time Clocks. These are quite nifty, alough overkill really, very good for the newb, as you don't have to worry about providing a backup powersupply, some just require a big capacitor, some even have Li-ion batteries built inside! An RTC will keep the time for you, and even manage alarams, it also has all the date functions you can want including leap year logic and such. Now this is totally overkill for this project. A watch crystal the slower the better, 32.768khz is probably the easyest to get. As long as your not wanting to do say PWM to dim the LEDs you will find this ample speed for your micro.
Yea I don't need to PWM the led's. I wonder if I should use a matrix display (to keep the size down) or get some small square led's and glue them to a peice of grey tint acrylic. I just want the display to look blank when its not on and then come to life when I turn the car on.
smoked glass, or acyrlic looks good i wouldn't glue the LEDs, i'd drill some softish wood or plastic with holes that the leds can be squeazed into, when you glue LEDs they often look ugly enless your sinking the LEDs into what ur glueing them too. Otherwise glue gets between the LED and the thing been glued to, and it looks ugly. I wouldn't worry too much about matrix'ing the LEDs enless you plan on having a lot of them.
I was just talking about using a matrix display (5x7 should be enough) because they are all bound together and then I could glue the whoal block along the edge to a peice of colored acrylic. Seem's easyer to me than doing a bunch of holes that I could drill off center lol. Do they make realy bright green matrix displays?
