7 seg led countdown

Thread Starter

masterchief

Joined Aug 19, 2006
3
hi, I am building a countdown unit for my paintball marker.It holds 99 balls
in the clip . i would like to use the 4511 cmos and 2 7 seg led common cathode. I need to know what chip would be needed for the countdown input
this is what I it to do
1. on power up w/ clip removed shows 00.
2. when clip is installed goes to 99
3 . when trigger pulled count goes down, marker can cycle as fast as 30 cyc pe sec.
4. for night games the display needs to be blanked out, the 4511 chip has that capability.
now for the fun part

I know you could build a unit w/ a pic controler with all the bells and wisles
and a lot less parts, i dont know the ist thing about about programming
if any knows who could write the program i would like it to do this

1. pwr up
2. clip removed shows00
3. cilp install shows 99
4. counts down 1 for ever input
5. when count gets to 10 flashes led
6. when clip removed led shows 00
7. have a provision for dimming
8. have a night mode, led stays off until you press a switch


if any one would like to help me w/ this programing



thanks alot mc
 

beenthere

Joined Apr 20, 2004
15,819
Hi,

You can do the counting with a couple of 40160 decimal counters. The other functions can be done in CMOS as well. CMOS will run into the 10's of megahertz, so 30 Hz is no problem.

How are you sensing the paint balls as they are fired? That might be the hard part.
 

Thread Starter

masterchief

Joined Aug 19, 2006
3
I am going to use the sol output of the marker, running through a reed relay
or a a solid state relay. what ever is easer.
probily will need some type of debounce w/ the reed relay,
 

beenthere

Joined Apr 20, 2004
15,819
Hi,

I don't have the details on the solenoid circuit, but the circuit attached should do the trick. I set Vcc for 12 volts, but the logig will work with anything between 5 volts and 18.

Got the counter wrong in my first reply - now it's a 4510 up/down counter.
 
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