hi noobie to the forum
- Thread starter scrivs
- Start date
Fete is 2nd week of July but my mate needs a couple weeks to have a go at it.
http://www.ebay.co.uk/itm/251509124...eName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
That's the leds
http://www.ebay.co.uk/itm/251509124...eName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
That's the leds
Unfortunately, those won't work, at least not the way you're intending. Those LED's have a built-in controller and change colors at random - see the video (link in eBay posting). We could use the microcontroller to turn them on and off, but there is no way to control the colors.
You could use these for a sign to draw visitors to your booth, you just need some resistors, wire, and a battery pack. You could also put them around your safe door as bling, but they might distract/detract from a player entering in a code.
I'll find some LEDs that will work from the site you linked to earlier. Again, I need a little time to flesh out a design then I'll provide you with a shopping list so you can get everything at one time. I'll aim to have an initial design and shopping list in a week and hopefully a prototype (to verify code and design) in two weeks. That should give you enough time to order parts, have your buddy build a circuit, and you get it into your safe.
If you could post drawings or pictures of the safe you plan to build, it will help determine where the parts will go, e.g., if the circuit board will be behind the display/keypad vs some distance away requiring longer wire lengths, etc.
My plan is to have say a board 1500mm x 900mm, at the top of this have a box with the digit display and the red and green leds ( 10mm rgb's ) to signify right and wrong this would then connect via cable to another box approx a third of the way down the board with the keypad in. The leds I have ordered around the outside to add as you say bling
Also I have been given a number from a friend regarding making a board professionaly by a PCB maker just 2minutes from the school so might appeal to them to help their local school. So when you get schematic drawing I will email it to them ( nothing to lose )
The ebay listing suggests a 470 ohm resistor for a 12V supply. It gives the forward voltage (2.8 - 3.2V) but i could not see the forward current so it's hard to be exact. However if it is OK with 470ohm at 12V then 330ohm should be fine at 6V (4x1.5 batteries) for example.
Because the PICAXE will need between 4.5-5.0V, my current plan is to use a 4.5VDC battery pack which will consist of three AA or AAA batteries. Using a 4.5V supply, 100Ω resistors will work fine for those LED's. Note due to the low voltage, the LED's will need to be connected in parallel with a resistor for each LED.
hi are these resistors ok for them leds i bought, ( is the price what you would expect to pay for them ) just want to get some soldering practice in.
http://www.ebay.co.uk/itm/290977136...49&var=590159244285&ssPageName=STRK:MEBIDX:IT
http://www.ebay.co.uk/itm/290977136...49&var=590159244285&ssPageName=STRK:MEBIDX:IT
thank you ordered.
this link was sent to me meant to be cheap and reliable http://stores.ebay.com/tekno-networks
Not withstanding the fact they are SMD resistors (very small, no leads), look at the item location and shipping costs, then go back CPC and buy what you need.
A lot of ebay UK sellers are buying from CPC/Farnell/RS and then reselling. This works in the case of parts that are only available from Farnell/RS because they have a minimum £20 order and are overpriced unless you have an account or buy in bulk.
A lot of ebay UK sellers are buying from CPC/Farnell/RS and then reselling. This works in the case of parts that are only available from Farnell/RS because they have a minimum £20 order and are overpriced unless you have an account or buy in bulk.
Alrighty, with some much appreciated help from the PICAXE forum, I have a demo working. Here is a video.
I'm still working out a few details namely getting the servo to operate and determining how best to allow the OP to change the code. I was originally thinking of having the OP enter in a special code, which is certainly doable, but I'm wondering if it would be simpler to prompt the OP for a new code on power-up. In this way, if the code was forgotten, cycling power (turning it off then on again) would reset the code and could prompt the OP to enter in a new code at power up. What do you think OP? This would mean after someone won, you'd turn the circuit off then on then you'd be prompted to enter in a new code.
To date, a user enters in four digits which show up on the display. After the fourth digit is entered, the program determines if any of the digits in their respective place are correct and turns the LED above the correct digit green. Incorrect digits are lighted red and the piezo buzzes three times to indicate an incorrect code and give the player a chance to remember which digits where correct. After the incorrect buzzer goes off, the display and LEDs go blank.
If a user enters in the code correctly, I have the piezo play a quick Mission: Impossible theme. Still working on the servo operation.
A few notes:
A servo requires a separate power supply since they are electrically noisy, hence the 3xAA and 4xAA battery packs.
As it turns out, while a piezo will operate as low as 3VDC, the sound is not very loud using the 3xAA battery pack, so I used the 4xAA battery pack which makes it louder. In a fete environment, I'm not positive this will be loud enough, so yet another battery pack may be needed.
Once I get the servo working, it may also be a good idea to simply stop the program once the safe is opened. This would require cycling power as mentioned earlier, but it avoids us having to worry about adding codes or commands to open then close the servo. At power-up, we can simply tell the servo to close (lock safe). When the correct code is entered, the servo will open and the program will stop until power is cycled. This okay?
Based on the video, thus far, does the circuit operate as you envisioned?
I'm still working out a few details namely getting the servo to operate and determining how best to allow the OP to change the code. I was originally thinking of having the OP enter in a special code, which is certainly doable, but I'm wondering if it would be simpler to prompt the OP for a new code on power-up. In this way, if the code was forgotten, cycling power (turning it off then on again) would reset the code and could prompt the OP to enter in a new code at power up. What do you think OP? This would mean after someone won, you'd turn the circuit off then on then you'd be prompted to enter in a new code.
To date, a user enters in four digits which show up on the display. After the fourth digit is entered, the program determines if any of the digits in their respective place are correct and turns the LED above the correct digit green. Incorrect digits are lighted red and the piezo buzzes three times to indicate an incorrect code and give the player a chance to remember which digits where correct. After the incorrect buzzer goes off, the display and LEDs go blank.
If a user enters in the code correctly, I have the piezo play a quick Mission: Impossible theme. Still working on the servo operation.
A few notes:
A servo requires a separate power supply since they are electrically noisy, hence the 3xAA and 4xAA battery packs.
As it turns out, while a piezo will operate as low as 3VDC, the sound is not very loud using the 3xAA battery pack, so I used the 4xAA battery pack which makes it louder. In a fete environment, I'm not positive this will be loud enough, so yet another battery pack may be needed.
Once I get the servo working, it may also be a good idea to simply stop the program once the safe is opened. This would require cycling power as mentioned earlier, but it avoids us having to worry about adding codes or commands to open then close the servo. At power-up, we can simply tell the servo to close (lock safe). When the correct code is entered, the servo will open and the program will stop until power is cycled. This okay?
Based on the video, thus far, does the circuit operate as you envisioned?
I think we're picturing different things.
Since the display is small (14.2mm high digits), I thought you'd want to use small LED's (5mm) to go right above each digit as shown in the video so the player could easily see which digits were or were not correct.
As you've drawn and you're describing, it sounds like you want a large LED indicator for each digit. Is this correct? Is this so others can see when a code was entered in correctly or not? If so, yes you can use a larger indicator or cluster of LED's, but it might be harder for the player entering the code to see which digits were correct or not vs. a single LED above each digit. In order to do this, we'll need to add a transistor for each LED to handle the current requirements. If you go with a large pre-made indicator, you'll more than likely need another battery pack with more batteries to get a higher voltage.
In the future, you could make your own 7-segment display out of LED's and make it large, say 25cm tall digits. Then a large indicator would work well and passersby would easily see it (and hopefully want to give it a try).
The one you linked to requires wall power since it is rated for 240V. You can probably find automotive LED indicators which will run off of 12VDC (8xAA batteries). Note a large indicator may eat through your batteries.
I've assumed you won't have access to an outlet and will need batteries - is this correct?
If you're not going to make a safe, do you still need a servo? What are you planning to do now? What is it you want to happen when a correct code is entered?
Is cycling power to change the code acceptable?
Since the display is small (14.2mm high digits), I thought you'd want to use small LED's (5mm) to go right above each digit as shown in the video so the player could easily see which digits were or were not correct.
As you've drawn and you're describing, it sounds like you want a large LED indicator for each digit. Is this correct? Is this so others can see when a code was entered in correctly or not? If so, yes you can use a larger indicator or cluster of LED's, but it might be harder for the player entering the code to see which digits were correct or not vs. a single LED above each digit. In order to do this, we'll need to add a transistor for each LED to handle the current requirements. If you go with a large pre-made indicator, you'll more than likely need another battery pack with more batteries to get a higher voltage.
In the future, you could make your own 7-segment display out of LED's and make it large, say 25cm tall digits. Then a large indicator would work well and passersby would easily see it (and hopefully want to give it a try).
The one you linked to requires wall power since it is rated for 240V. You can probably find automotive LED indicators which will run off of 12VDC (8xAA batteries). Note a large indicator may eat through your batteries.
I've assumed you won't have access to an outlet and will need batteries - is this correct?
If you're not going to make a safe, do you still need a servo? What are you planning to do now? What is it you want to happen when a correct code is entered?
Is cycling power to change the code acceptable?
Yes my thinking is to draw attention to people watching around the stall, but was thinking leds near the keypad then like spared off to the seperate led box.
Yes would like a servo then at least I have the option to use or not for the summer fete.
I could if needed ask for a in door table then could use mains power.
Turning the unit off to reset it is not a problem.
Yes would like a servo then at least I have the option to use or not for the summer fete.
I could if needed ask for a in door table then could use mains power.
Turning the unit off to reset it is not a problem.
