basic help project

[gary2530]

want to build a electronic counter but not a simple one,i have very little knowledge of this sort of thing i will try to explain what i would like to do if some one could help in basic english i would be greatful.to start with a pressure pad the one you find in alarms would be the switch to turn on a light the light would have to stay on even if the pressure is removed from the pad ,thats the first problem.next to turn the light out would be a seperate device ,each time it turned the light out it counted the number of time it was used being able to zero it when needed to .the pressure pad & light need to be portable may be 9v or so the reset counter can be what ever.thanks for reading

 

[GreenGiant]

well for the first part youre probably better off using a flip flop, J/K to be specific, the first button will latch the output high, then the second will trip the reset.

The second part might be a little tricky, but if you use a counter IC that reads on the falling edge you can monitor how many times it goes from high to low

The outputs from a J/K flip flop is 5 volts so that would handle an LED with a small resistor no problem

 

[CocaCola]

This could easily be accomplished with a small µ-chip, but that would require you have experience and tools to work with them... Counting beyond a few trips with traditional components will complicate the circuit exponentially vs using a µ-chip, thus personally I would venture away from that type of design...

There is also more specifics that need to be disclosed, for example should the number of triggers be displayed or should it be able to read out via the reset tool? How high should it count? Are you thinking two devices? If so how do they interface? Are they plugged together, wireless, IR? Lots of variables that need to be clarified...

 

[GreenGiant]

This could easily be accomplished with a small µ-chip, but that would require you have experience and tools to work with them... Counting beyond a few trips with traditional components will complicate the circuit exponentially vs using a µ-chip, thus personally I would venture away from that type of design...

There is also more specifics that need to be disclosed, for example should the number of triggers be displayed or should it be able to read out via the reset tool? How high should it count? Are you thinking two devices? If so how do they interface? Are they plugged together, wireless, IR? Lots of variables that need to be clarified...

I was trying to avoid the microcontroller route as they said they have no experience, and also microchips usually take more power than just small IC's

the circuit that I recommended (depending on what parts were selected) would be able to count into the hundreds of button presses, there are some simple counter IC's that will count up to 255 and more

 

[gary2530]

yes i need two seperate devices ,pressure pad/switch & light are portable,counter/reseter can be static how they communicate is up to you,but the pressure pad side of it will come back to the counter to get the light turner off the counter max. should be 999 with a reset that can be only reset by some sort of restricted access.code key ect.numbers on the counter can be visible to everyone.

 

[olu1yomi]

please i need component data sheet book ,how can i get 1?

 

[CocaCola]

also microchips usually take more power than just small IC's

Todays µ-chip powder drain in an idle sleep mode is insignificant in almost all cases, the batteries self drain is larger...

Microchip has active current chips in the 150µA range with 10nA pull in sleep, hardy a concern in most any project... The count display will be the real drain on the system...

there are some simple counter IC's that will count up to 255 and more

But, you still need the display drivers to make the count visible, and the requirement for an admin type reset further complicates it... Sure you could do it with more discreet chips, but I hate fighting the future as a single micro will do it all for about a $3... I know the age old fight of just coping out and using a micro when discreet components will work irks many old timers, but it's really the future of electronics $ for $ and labor wise and I'm not one to fight it...

Back to gary2530, you have a tall order for the design and one that is almost certainly beyond your means unless you really start crunching the books and websites for a crash coarse in electronics...

Overall it's not an overly complicated circuit to design with a micro, in fact it's pretty basic and small loop as you are simply watching a single port for a logic transition and counting... The reset device with a login is a little more complicated but unless high security is needed it's still not hard...

please i need component data sheet book ,how can i get 1?

Contact the manufacture of the component