urbex Posted April 28, 2011 Report Share Posted April 28, 2011 Ok, well I've got EVERYTHING the way it should be...all set up right, connected right, and I even now have 12v connected to the timer circuit just in case...still NOTHING. It reads zero, but as before on initial contact of the wires to the VSS, it will read a few mph, but then immediately drop back to 0mph.... I really have no idea what else I could do to get this to work.... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 29, 2011 Report Share Posted April 29, 2011 it almost sounds like the 555 was setup wrong... as if it were put into monostable mode, instead of astable... Quote Link to comment Share on other sites More sharing options...
urbex Posted May 9, 2011 Report Share Posted May 9, 2011 (edited) Ok, well I kind of put this project on hold due to frustration. Well, got it back out today. I can't really read that chart that easily, and since school is out I've got no one there to ask... As for the resistors, according to that chart, which holes (or whatever you call the 1-8 on the timer) would I plug the resistors into? Resistor 2 goes from 6 to 7, but resistor 1 has both ends in 6...which I don't think is right? Obviously something has to be wrong with my circuit, since like I said before I can get the speed to change, only on initial contact though.... Like I said, I'm not good at reading the chart, but according to that shouldn't the capacitor go from 6 to ground? On mine it's set up as 7 to ground....? Edited May 9, 2011 by urbex Quote Link to comment Share on other sites More sharing options...
GnatGoSplat Posted May 9, 2011 Report Share Posted May 9, 2011 Ah, I think you're reading the schematic wrong. R1 connects to pin 7 and 8. It doesn't touch 6. When there is a line intersecting another line, there is no connection there unless there is a dot. For example, the wire they show connecting pin 2 to 6 does NOT connect to 4, 7, and 8 because there is no dot. Now, if the line doesn't intersect, then it doesn't need a dot to show connection. For example, VCC does connect to both 4 and 8. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 9, 2011 Report Share Posted May 9, 2011 Thanks! That did clear up quite a few things for me. I tried adjusting some stuff that was obviously wrong...but it still doesn't work. To make sure I'm on the same page, the VCC is the power supply to the circuit, (my 9v battery) correct? So, the capacitor is connected to pin 6 and ground, correct? Then my one other question, is what do those two black lines represent on pin 5? Mine is set up so there's a wire connecting 5 to ground....? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 9, 2011 Report Share Posted May 9, 2011 the "black lines" on pin 5 are connected to a .01uF capacitor, which has a leg that connects to ground. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 9, 2011 Report Share Posted May 9, 2011 Oh wait...now I got more confused again... I thought the Capacitor went from 6 to ground? So what do the two lines represent next to C1 on the diagram? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 9, 2011 Report Share Posted May 9, 2011 there are two capacitors in the circuit, C1, which is calculated to be .01uF, and the one on pin 5, which should also be .01uF. try disconnecting the pin 5 connection from the circuit. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 9, 2011 Report Share Posted May 9, 2011 Well then, I'm thinking I may have figured out what's wrong. (Well, actually you did...lol) I only have 1 capacitor. Which really sucks, because I couldn't find it anywhere like Radio Shack, so I had to order it online....yay shipping that is more than what you're buying.... Otherwise it appears that everything is right like the diagram says... What I have now is just wiring from pin 5 to ground, no capacitor. I'm hoping then if I switch that to another capacitor it should work.... I did disconnect pin 5 from the circuit, but it did nothing. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 9, 2011 Report Share Posted May 9, 2011 the cap on pin 5 is there to prevent false triggers IIRC. disconnect and reconnect wires when you have the circuit powered up, see what all will get the cluster to react. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 9, 2011 Report Share Posted May 9, 2011 Well I hooked everything up and tried unplugging and replugging the wire in pin 5, but it never read anything other than 0...so I'm guessing I've got something else screwed up other than the capacitor. The only other thing I can think is maybe I fried something else when I blew the timer... Quote Link to comment Share on other sites More sharing options...
GnatGoSplat Posted May 10, 2011 Report Share Posted May 10, 2011 You'll still need that 10nF capacitor from pin 6 to ground. And yeah VCC is the positive lead of your power source. If you need a 10nF capacitor, I can mail you one or a few. And any resistors you may want as well. I have a bin full of stuff I've scavenged from junk electronics. When I think of it, I'll compare to my setup to see if I used the same components or different. Main difference is I had made mine variable because I didn't know what the max speed the cluster would support. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 13, 2011 Report Share Posted May 13, 2011 If you could send them to me, that would be AWESOME!!! I can give you a few bucks for them, just let me know how much. Quote Link to comment Share on other sites More sharing options...
GnatGoSplat Posted May 13, 2011 Report Share Posted May 13, 2011 PM me your address. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 13, 2011 Report Share Posted May 13, 2011 Ha ha, sorry I meant to send you a PM yesterday, but I got sidetracked....lol. PM Sent! Quote Link to comment Share on other sites More sharing options...
jimmyfloyd Posted May 24, 2011 Report Share Posted May 24, 2011 Does any one have the pin outs for the connectors to the Digital cluster? I want to test the one I have here. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 25, 2011 Report Share Posted May 25, 2011 Ok.... I finally got some time to fiddle with this damn thing again... Now I put the .01uf capacitor from pin 5 to ground, and I have another .01uf capacitor from pin 6 to ground. 270k Ohm resistor from pin 6 to 7, and 27k Ohm resistor from pin 7 to 8. Pin 1 is connected to VCC, pin 2 is connected to pin 6, pin 3 goes to the cluster, pin 4 is connected to VCC and pin 8 is connected to VCC. I have no idea what else I could be doing wrong.... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 25, 2011 Report Share Posted May 25, 2011 (edited) pin1 is connected to VCC? EDIT: also is R1 connected to both pin4 and VCC? it should be. Edited May 25, 2011 by RobertISaar Quote Link to comment Share on other sites More sharing options...
urbex Posted May 25, 2011 Report Share Posted May 25, 2011 (edited) Ooops, sorry, I misspoke. Pin 1 is connected to ground, sorry! I only have pin 4 connected to VCC via jumper wire. No? I need another resistor there? I'll switch it over to a 27k Ohm resistor and see what happens... EDIT: Nope...replaced the jumper wire on pin 4 to VCC with a 27k OHM resistor, and nothing... Edited May 25, 2011 by urbex Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 25, 2011 Report Share Posted May 25, 2011 hold up... pin 4 is the reset pin, and when it gets toggled, that's what allows the pulse train to continue functioning.... since it works for a fraction of a second on initial start, i'd say your connection related to pin 4 is the problem... look at the diagram again: pin 4 is connected to VCC, pin 8 and the side of R1 that isn't connected to pin 7, make sure all of these are correct. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 26, 2011 Report Share Posted May 26, 2011 AAAHH!! I've got R1 going from pin 7 to pin 8... So I need another R1 going from Pin 4 to VCC. So I need a total of 3 reistors in this, correct? One going from Pin 4 to VCC, one going from Pin 7 to pin 8, and one 270k ohm going from pin 6 to 7? Or am I just screwing this up more? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 26, 2011 Report Share Posted May 26, 2011 there should only be a total of 2 resistors... pin 4 and pin 8 should be connected directly to VCC. pin 7 is connected to VCC through R1. pin 6 is connected to VCC through the R1 R2 chain. you should have some type of jumper connecting pin 2 to the pin 6 circuit somewhere between the pin itself and R2 or C1. pin 5 is connected to a capacitor which is connected to ground. pin 1 is connected directly to ground. C1 has one lead connected between R2 and pin 6, the other lead is connected to ground. finally, pin 3 should be hooked up to the instrument cluster's 4K PPM circuit. if any of these things are not true, make them so. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 26, 2011 Report Share Posted May 26, 2011 Well, I am honestly at a loss. Everything is hooked up exactly as you said, I've triple checked. But nothing! Just reads damn 0 on the cluster. I just have no idea what else I could be fucking up.... Thank you again for all your help, I really do appreciate it... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 26, 2011 Report Share Posted May 26, 2011 hmm...... and 555s are actually one of the easiest IC's to set up.... guess you may have to do a 3-wire computer fan trick.... draws more power and is in no way adjustable(other than varying the voltage supplied to it), but it may be your only option. Quote Link to comment Share on other sites More sharing options...
urbex Posted May 26, 2011 Report Share Posted May 26, 2011 I agree....this 555 isn't going to work... What will I need to make the computer fan? Obviously a fan, lol But I mean, do I use the same wires I used as jumpers? Do I attach it to a breadboard? How many volts to supply it? 9v? I can probably run to Radio Shack tomorrow after work and get any parts I will need... Quote Link to comment Share on other sites More sharing options...
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